The Otos accepted food

I’m pleased to say that the Otos decided to accept food from me for the first time.

At first they didn’t accept the Wels-Chips, they didn’t react to flake food either.

So I got a few Pleco-min tablets from the other tank(wich is in my girlfriends house), to see if they’d accept that.

When I threw in half a tablet, there was a reaction, they searched the glass and the plants in the area, but didn’t go to the tablet.
El Gigantea, the largest shrimp took the tablet and ran with it. Defending it from the other shrimp, who were only allowed to eat the crums she dropped.

Later that night I threw in two quarters of the tablet, without an immediate respons. I was immediately dissapointed by my impacience, but then I saw they were searching for it again.

And this time one of them found it, nibbled it, searched the area around it, but then seemed to firgure out it actaully was the tablet.
A good 10 minutes later the other one found it too.

The second quarted went to the large shrimp again.

The day after that I rubbed a Wels-Chip with a bit of Plecomin, and dropped it in the tank.
The Search went on immediately, but it took 30 minutes for one of ‘m to find it. Or accept it. This morning it was gone, I don’t know who ate it, but at least I saw one of them eat from it.

I have prepared the next meal by squishing up a quarter of Plecomin in a few drops of water. And smeared it over a Wels-chip.
I wonder if they will ever start to fancy the Wels-chip. Otherwise this hase been my last try and I will have to see that I get more Plecomin or other Spirulina tablets.

Green Algae

Begin of this week I started to notice these green algae on my window.
The Oto’s are on this side of the glass a lot but they don’t seem to eat it, or are unable to get it of the window.




I’ve tried myself, and it doesn't come of easy. I could only get it of with a circular motion of the sponge/scrubbing-pad. The Scraper doesn’t seem to do anything to the algae.

So I did a waterchange, and closed the curtains to see how it will grow without the sunlight.

After the maintenance I noticed that I’ve failed to remove all of the algae. It’s been two days, and I can say it seems to grow at a very slow rate if at all. At the next waterchange I will remove it again, hopefully completely this time, and keep the sunlight of the tank for another week.

As long as it’s controllable this way I won’t do anything radical like use algizit or take out the nutrient soil.

AquaClean 3in1

Didn’t have an algae magnet, so I went to the store and saw this thing for about the same price. I thought I’d give it a shot.
Looks like a handy thing, and with this I could even scrub the backwall.

Manufacturers description
The SF AquaClean ensures easy aquarium maintenance without getting your hands wet.


The 3 accessories, an algae scraper, a glass cleaning spouge and a gravel rake, make the aquarium maintenance as simple as can be. assemble the handle and accessory holder to the rod and then choose which accessory you want to fit to the holder - these are esaily interchangable.

Bought at: Pet’s Place
Brand: SuperFish
Price €: 4,95

Quick update 28.08.07

Scrubed the algae of the glass. And will not let any sunlight hit the tank for a while.

I also set the Heater on 25 degrees, since this is more in the middle range for the Shrimp and Otos, and therefore alows more fluctuation. At least that's what I think.
The temperature will now pendle between 25 and 25 degrees celcius.

Did a water change, and cut one stem of Rosealfolia, and pennyworth. These stems I brought to my community tank, since I don’t have the space for it.
I’d like to have more roseafolia in the back, but to acchive that I have to move the Pennyworth.
The Rosealfolia might not be Alternanthera reineckii afterall, but Alternanthera Cardinalis. I’d have to investigate if it’s a big difference but I fugre it won’t be.

Perhaps I’ll do some reanging when the wood come in, and the foregroundplants are no longer worth taking care of.

Hemianthus callitrichoides ”Cuba” – a beautiful carpet in AquaCube and in the aquarium

Found on: www.tropica.com

By Troels Andersen

This species of Hemianthus quickly forms a low, dense and brightly green carpet covering the bottom of the aquarium. Oxygen bubbles form on leaves resulting in vivid reflections of the light and in this way, a perfect foreground decoration is formed. Hemianthus callitrichoides may be planted directly into the substrate or attached to pieces of rocks and driftwood and it is suitable for large as well as small aquaria.

Photo by Oliver Knott

Hemianthus callitrichoides (048B) was recovered by Tropica’s founder Holger Windeløv during the dry season in a rocky river not far from Las Pozas about 90 km east of Havana in Cuba. Here, it was rooted in gravel between large rocks about 50 cm above the current water level of the river. The plant appeared as a dense pad shaped population very resistant to the heavy drag forces of the water which would have flooded and submerged the group of plants to about 1 meter depth during the rainy season. According to our information, Hemianthus callitrichoides is only found in Cuba, whereas Hemianthus micranthemoides (048A) is also found elsewhere in North America. Hemianthus callitrichoides belongs to the family of Scrophulariaceae and is thus closely related to Callitriche which has a more northern distribution.

Hemianthus callitrichoides forms low pads (3-6 cm) and thus, it is quite different from Hemianthus micranthemoides by having much shorter internodes but also smaller leaves. Hemianthus callitrichoides forms a unique flower which makes it easy to identify. With only 4 petals (versus 5) and only one central chamber in the fruit (versus 2) Hemianthus callitrichoides is easy to distinguish from Hemianthus micranthemoides. In addition, the leaves of Hemianthus callitrichoides are darker than those of Hemianthus micranthemoides.

Tropica grows Hemianthus callitrichoides in emergent cultures in stone wool and on coir fiber discs for the AquaCube. Hemianthus callitrichoides should be planted in large adjoining groups in the foreground of the aquarium. One pot grown in stone wool is easily divided into 7-8 portions which are then planted with a distance of a few cm. Within 3-4 weeks the plants will cover the bottom forming a beautiful green carpet. Likewise, Hemianthus callitrichoides is very suitable for the AquaCube where the oxygen bubbles contribute to the ornamental effect.

Hemianthus callitrichoides is not particularly light demanding, but the more light we provide, the more compact the growth form. Under limited light, the plant grows a bit longer (up to 20 cm). Hemianthus callitrichoides is fast growing and thus, it requires fertilizer (typically after 3-4 weeks) unless you have many fish in the aquarium. Iron deficiency is common and is recognized by the new leaves being yellowish. However, the deficiency is easily treated by using PLANT NUTRITION liquid in the recommended doses. At intense growth pruning may be necessary and it may be done like pruning grass. Like in most other cases, extra vivid growth is obtained by adding CO₂ but the beautiful oxygen bubbles are often formed also without using CO₂ enrichment. Hemianthus callitrichoides has its optimum temperature around 25 ºC but it thrives well from 20 to 28 ºC.

Hemianthus callitrichoides is perhaps one of the best and easiest foreground plants we have because it quickly forms a low carpet and the ornamental effect is highly improved by the oxygen bubbles which easily form on the leaves. However, many faster growing plants may overgrow Hemianthus callitrichoides and thus, it is necessary to prune neighboring plants every now and then.

Hemianthus callitrichoides is relatively new in our hobby and thus, the information about it is scarce. Hemianthus callitrichoides is botanically described in a Spanish flora (Flora de Cuba) and a few experiences from the aquarium are listed in the literature below.

Literature:
Kramer H G (2003) Hemianthus callitrichoides (flora aquatica). Aquaristik Fachmagazin 169: 74, in German

Limnophila aquatica "Giant Ambulia"

I got these stems of giant ambulia from my favorite fishstore. I have received stems of this plant previously. Those are in the other tank and have made new tops.
These don’t have a proper root system yet, but I’m in good faith that they will make new tops too.

I’m very glad to have received these stems for free twice. They are very hard to come by. I haven’t found a single store that sells them, since the retailer doesn’t have them in their collection. No clue as to why. It’s a very pretty plant.

And it’s actually a local plant for the Indian dwarf puffers.

Family Scrophulariaceae
Continent Asia
Region South-east Asia
Country of origine South-east Asia
Height 25-50 cm
Width 9-15 cm
Light requirements medium-very high
Temperature 20-30 °C
Hardness tolerance very soft-medium
pH tolerance 5-8
Growth fast
Demands medium

An extremely beautiful aquarium plant circled by light-green and finely branched leaves. In the right growing conditions with added CO2 and a nutritious bottom this plant grows fast. In good light it forms horizontal side shoots and becomes attractive and bushy. Most decorative when several stems are planted in a small group. In open aquariums it sometimes sends shoots above the water surface, forming small blue flowers.

Bought at: Het Natuurhuis
Brand: No brand
Price €: 0,00

Hemianthus callitrichoides

The start looked promising and I thought I might actually grow a carpet.
Its still alive, but its not very compact, and growing slightly upward. Again a light issue?

I will defiantly try it again, but this time growing it on wood or sponge first.

Family Scrophulariaceae
Continent South America
Country of origin Cuba
Height 5-3 cm
Width 3-10+ cm
Light requirements low-very high
Temperature 18-28 °C
Hardness tolerance very soft-hard
pH tolerance 5-7,5
Growth medium
Demands medium

Hemianthus callitrichoides is one of the smallest aquarium plants in the world, and creeps over the bottom with millimetre-sized round leaves. If planted in small clumps a few centimetres apart, it will spread rapidly and cover the bottom like a carpet. Hemianthus callitrichoides is an attractive foreground plant for small aquariums, and makes few demands. Found on Cuba west of Havana.

Bought at: Intratuin.
Brand: Aquafleur
Price €: 2,16

Glossostigma elatinoides

This plant doesn’t really work in my cube. Half of it died, the other half looks fine, but grows upwards, and doesn’t really look like one plant. Just little stems and strains here and there. It recieves all the light I can give it. I think it will eventually have to be replaced with something else.

“Grows to a height of 2 to 3 cm (FOREGROUND)
The width of each plant is about 3,5 cm, based on leaf growth
Medium high to very high lighting (2.5 - 3.5 watts/gal)
Optimum growth temperature is 22 to 29 degrees

Glossostigma elatinoides is much in demand in Japanese-inspired aquariums. It is one of the smallest aquarium plants, and thus a good foreground plant. A difficult plant demanding a lot of light. Grows upwards if light is poor. Make sure larger plants do not overshadow it. When planting in the aquarium small clumps (approx. 1/8 pot) should be placed at intervals of a few centimetres to help the plants grow together more quickly. CO2 addition and soft water promote growth significantly. (Excerpt From Tropica)

Glossostigma elatinoides is a medium difficulty stem plant that will thrive in aquariums with adequate lighting and not too hard water. The plant typically grows to a height of only 1.2 inches.The width of each leaf is about 1.2 inches, based on leaf growth.The leaf is petiolate.

In order to achieve strong shoots the substrate should be nutrient rich and light intensity high. Specimens should be planted individually spaced apart and will then grow in. while it may be painstaking to plant them individually, it is well worth the effort. Optimum growth temperature is 72 to 79 degrees, although it can grow in temps from 59 to 79 degrees.

Glossostigma elatinoides requires medium high to high lighting (2.5 - 3.5 watts/gal) to do well. If kept in low-light tanks, this aquarium plant has a tendency to wither away. Separate each stem and plant individually. This will result in better growth and help Glossostigma elatinoides to spread.

Don's Notes:

My experience with Glossostigma elatinoides is that it grows better with iron nutrients in the substrate. I have floated little pieces of stem on the surface and had them continue to grow and then planted them in the substrate. Glossostigma elatinoides only requires sufficient fertilizers and an adequate source of the gas CO2 (carbon dioxide), or a good liquid carbon substitute like Excel or Natural Aquarium Vital. It also likes water that is not too hard. The leaves are a beautiful shade of bright green, making it an excellent foreground plant for higher light aquariums. In lower light the plant tends to grow upward as if to reach the light, and eventually withers away.

This aquarium plant comes from New Zealand, Australia, and Tasmania.”

Don Matakis is the Aquatic Grower & Senior Aquaculturist for freshwateraquariumplants.com

Bought at: Intratuin.
Brand: Aquafleur
Price €: 2,16

Echinodorus Uruguyanensis africanus

Another plant I’m not sure of, but i think it’s an Echinodorus Uruguyanensis africanus.

Al leaves where flat when I got it, now alot are abot wrinkly, I added some fertilizer, but that didn't help. It looks healthy, I just thought it might be missing something.


Family Alismataceae
Continent South America
Region South America
Country of origin South America
Height 20-55+ cm
Width 10-30 cm
Light requirements medium-very high
Temperature 15-26 °C
Hardness tolerance soft-hard
pH tolerance 5-8
Growth medium
Demands easy

Echinodorus uruguayensis has long, narrow, transparent, dark-green leaves, making it a very beautiful solitary plant for large aquariums. The leaf length and width vary considerably. In good growing conditions it forms an unusual number of leaves, and a nutritious bottom and CO2 addition and slightly acidic water promote growth. A number of species formerly regarded as distinct are now included under the name E. Uruguayensis

Bought at: Intratuin.
Brand: Aquafleur
Price €: 2,16

Ophiopogon japonica

After I planted this plant I immediately liked it. After doing some research on it, I found out it’s not really an aquatic plant, and will probably have to be replaced within a few months to a year.
I hate it when they do that, the plants are cheaper at the local garden centre, but you’re never quite sure what you are getting.

I’ll just see how it works out first before replacing it.
Until now it seems to do fine. It was troubled by some green algae first, but the Oto’s and shrimp took care of that.

“A terrarium plant sometimes used in aquariums and goldfish bowls. Can be used as a decorative plant, but only lasts a few months. The good balance of an aquarium is disturbed if there are too many of these plants."

Not eaten by herbivorous fish.

Family Liliaceae
Region Asia
Land Japan
Height 10-30 cm
Width 15-25 cm
Light medium-very high
Temperature 15-26 C
Hardness soft-hard
pH 6-8 pH
speed of growth slow
Demands medium

source: www.aquaticcommunity.com

Bought at: Intratuin.
Brand: Aquafleur
Price €: 2,16

Hydrocotyle leucocephala “Pennyworth”

Another plant that has previously fallen victim to the clown botias’, and I’m giving another shot here.
So far it’s doing fine, although it’s stealing light from all other plants, including itself, the small leaves at the bottom don’t really get a chance to grow. Even some large ones have turned yellow and fall off.
When the wood goes back in I must see if I can find another place for it.

Common Name: Pennywort, Brazilian Water Ivy
Native to: Southern Mexico to Northern Argentina
Height: 10 to 20 cm (up to 24 in)
Width: 5 to 15 inches, based on leaf growth
Growth Rate: Fast
Placement: Mid to Background
Lighting Needs: Low to high lighting (1.5 - 4 watts/gal)
Temperature: 20 to 28 degrees
Hardness: Does best in nutrient rich water, loves nitrogen
Difficulty: Easy

“Hydrocotyle leucocephala is an easy to grow stem plant that will thrive in all aquariums. Because it does not need to be rooted it can be used as a floating plant, providing a hiding place for young fry. It has been used as an herb in the tropics.
The plant typically grows to a height of 4 to 8 inches, even taller (24 in.) under high light conditions which has been my experience. The width of each stem is about 2 to 6 inches, based on leaf growth. The leaf is roundish to reniform and alternating.

This plant does well in all water hardness conditions and most lighting situations. Optimum growth temperature is 68 to 82.4 degrees, although it can grow in temps from 41 to 86 degrees. Hydrocotyle leucocephala requires low to high lighting (1.5 - 4 watts/gal) to do well. If kept in low-light tanks growth is slower. Plant either in the substrate or as a floating plant.
Don's Notes: My experience with this aquarium plant is that Hydrocotyle leucocephala is actually very easy to grow and is my personal favorite of all aquarium plants. This is a very tropical and exotic looking plant with a beautiful shade of green. Hydrocotyle leucocephala does better with a nutrient rich water column and loves nitrogen. If nutrients are low, growth seems to stall and leaves become smaller. Aquarists with a bit harder water might find that this plant grows very fast. For those with very soft water growth is not as rapid, although fine specimens can be grown. A beautiful addition to any aquascape! Hydrocotyle leucocephala is found in Southern Mexico to Northern Argentina. “

Don Matakis is the Aquatic Grower & Senior Aquaculturist for freshwateraquariumplants.com

Bought at: Intratuin.
Brand: Aquafleur
Price €: 2,16

Alternanthera reineckii ''roseafolia''

I bought this plant for my larger tank a few times, but it always got demonische, first by the clow botias, and now by the plecos I keep. (peckoltia vittata)

So I’m giving in one last shot here. Untill now it seems to be doing fine, it’s growing too high, I’ll have to do some pruning soon.

I’m not entirely sure the plant I have acutely is this Roseafolia, but it looks very similar to me

Family: Amaranthaceae
Common Name: Magenta Water Hedge
Native to: South American Amazon region
Height: 25-50 cm
Width: 10-15 cm, based on leaf growth
Growth Rate: Slow
Placement: Mid to Background
Lighting Needs: Moderate to high (2-4 watts)
Temperature: 17-28 °C
Hardness: Does best in soft, slightly acidic water
Hardness tolerance: soft-hard
pH tolerance: 5-8
Growth: medium
Difficulty: Relatively easy

“The purple colour underneath Alternanthera reineckii ''roseafolia'' leaves provides an effective contrast to the many green aquarium plants in an aquarium - particularly when planted in groups. Good light encourages the leaves to turn red. Most Alternanthera species are difficult to grow, but this one is relatively undemanding. Easy to propagate by nipping off the terminal bud and planting it in the bottom. This also makes the mother plant more bushy, because more side shoots are formed.
Alternanthera reineckii is an easy to grow stem plant that will thrive in most aquariums. The plant typically grows to a height of 10 to 20 inches, even taller under high light conditions. The width of each stem is about 4 to 6 inches, based on leaf growth.The leaf is oblong-elliptic to ovoid.

In order to achieve strong shoots the substrate should be nutrient rich and light intensity high. Three to five strong specimens can be used for the background area to help accent the shades of green aquarium plants. Alternanthera reineckii can grow well in both hard and soft water although soft, slightly acidic water is best. Optimum growth temperature is 75 to 80.6 degrees, although it can grow in temps from 71.6 to 82.4 degrees. It can withstand temps from 39.2 to 84 degrees.

Alternanthera reineckii requires moderate to high lighting (2 - 4 watts/gal) to do well. If kept in low-light tanks the lower leaves tend to fall off. Separate each stem and plant individually. This will result in better growth and the lower leaves will still receive some light as the this aquarium plant grows taller.

Don's Personal Notes: My experience with this aquarium plant is that Alternanthera reineckii is very easy to grow and quite strikingly beautiful when it has enough light. I have floated little pieces of stem on the surface and had them continue to grow and then planted them in the substrate. Alternanthera reineckii only requires sufficient fertilizers and an adequate source of the gas CO2 (carbon dioxide), and you are ahead of the game if you use Laterite or substrate nutrient balls or tablets in your aquarium. The leaves tend to grow in an upward fashion which really shows off the deep, beautiful red color! This aquarium plant is a cultivar of the original Alternanthera reineckii which comes from the South American Amazon region, and the easiest to grow of all the varieties.”

Don Matakis is the Aquatic Grower & Senior Aquaculturist for freshwateraquariumplants.com.

Bought at: Intratuin.
Brand: Aquafleur
Price €: 2,16

Otocinclus macrospilus

Two days ago, I introduced two Otocinclus to my cube. (I think they are O. Macrospilus)
They came in the same bag as the shrimp, and I had the bag acclimatise for only 15 minutes since it was a hot day.
And I always feel that sitting in a bag floating in a tank causes alot of stress.

Especially in a community tank, with the other residents looking and picking at the bag.

I like to give them a chance to hide in the plants as soon as possible.

But Allot of times they are so much in shock they just lay in front of the window.


Same here. One of them didn’t seem to have much of a problem, and sucked itself to the window and stayed there for about 15 minutes. The smaller one looked more in shock, and just lay on the ground, in close proximity to the other one, breathing heavily.

I left them a Wels chip, in addition to the brown algae in my tank, to make sure they had enough to eat.

Next morning I found my tank as clean as can be. All brown algae disappeared, just a little bit on the ophiopogon, but this they cleaned out the rest of the day.

The wells chip did get moved, but looked otherwise pretty untouched. I learned the other day that the shrimp like to move them, but don’t eat much of it.
The Otos both have a slightly rounded belly, so I’m not sure if they don’t eat the chip because they have plenty of other stuff to eat, or if they don’t recognize it as food.

I will try flakes, and plecomin in the next week.

I really like them, they sure live up to their reputation.
The larger one might be a female, I named him/her Max, the smaller one is called Moritz.

Species Information (found on planetcatfish.com):

Scientific Name	Otocinclus macrospilus Eigenmann & Allen, 1942 - add this species to your "My Cats" page.
Common Name(s)	Dwarf Sucker, Oto
Type Locality	Río Morona, Upper Amazon, Dpto Loreto, Peru.
Pronunciation	auto SINK luss - MAK ro spill us
Etymology	Greek, ous, oto = ear + Latin, cinclus = latticework; in allusion to the holes of the head in the ears
Species Information
Size	34mm (1.3") SL Show near, nearer or same sized spp.
Identification	Similar in overall colouration to O. vestitus. The caudal fin marking is key to separating this species of Otocinclus from the others.
Sexing	Females are larger and broader especially when viewed from above.
Habitat Information
Distribution	Upper Amazon Basin of Colombia, Ecuador & Peru Amazon, Upper Amazon (click on these areas to find other species found there)
pH	5.5 - 7.5
Temperature	21.0-26.0°C or 69.8-78.8°F (Show others)
Husbandry Information
Feeding	Initially algae, add a shoal to an ''algaefied'' tank and then supplement diet with sinking tablets and the usual cucumbers / lettuce or courgette (zucchini).
Furniture	Large leafed plants and vertical flat rock surfaces (especially slate). Not essential, but likes bogwood and a large rounded substrate. Live plants seem essential to the long term survival of this fish.
Compatibility	Peaceful.
Suggested Tankmates	Keep in groups (preferably at least six) with any small to mid-sized community fish.
Breeding	See Shane's World Article

http://www.planetcatfish.com/catelog/species.php?species_id=105

The Ideal Algae Eater? The Littlest South American Suckermouth Catfishes, Genus Otocinclus

Found on: www.wetwebmedia.com

By Bob Fenner

Of the thirty four living families of catfishes, a few stand out as aquarium favorites; the armored cats of the Callichthyidae (e.g. Corydoras, Diadema), the long-whiskered pimelodids, the gorgeous Synodontis of the family Mochokidae, and the "plecostomus" family of South American suckermouth catfishes, the Loricariidae. The loricariids are often called upon to do "double duty" as aquarium specimens; to look nice and be a/the clean up crew removing algae and other waste. This way too often doesn't work out as planned.

There are some principal misunderstandings regarding the loricariids; as basic as which species are which, what water quality they enjoy/will tolerate, and providing them adequate to appropriate foods. Many species are in taxonomic limbo and numerous (at least two to three hundred) are yet to be scientifically described. Some are huge, attaining more than two feet in length, and quite aggressive/territorial; fighting back any and all tankmates. Others, like the genus Otocinclus we'll be covering here, are small (a couple of inches maximum) and retiring.

In "browsing" the electronic bulletin boards regarding freshwater fishes, live plants and aquariums I've noticed a great deal of interest in these "little suckers"; and several references to lack of success in keeping them. The "formula" for Otocinclus success is actually not mysterious nor any secret at all. After handling hundreds of boxes of imports of these fishes, and observing attempts at their commercial production in the Far East, I've come to the this parsimonious conclusion. As is often the case with all livestock husbandry, the principal concerns are merely selection, proper water quality, habitat and feeding.

Classification: Taxonomy, Relation With Other Groups

The catfishes are a huge assemblage, some 34 families, 412 genera and 2,405 described species, making up the Order Siluriformes. Of these, the suckermoth armored catfishes, family Loricariidae, collectively termed "plecostomus" or "plecos" by hobbyists, are an enormous group themselves. The largest family of catfishes, with about 80 genera and 600 known species, some systematists subdivide the loricariids into five subfamilies based on head shielding characters (See Nelson, 1994, Burgess, 1989).

You know these fishes; dorso-ventrally (top to bottom) flattened, with underslung sucking mouths surrounding fleshy lips bearing reduced barbels, and spiny body armor ("loricar" means armored). Of special note are loricariid fish eyes; those omega-shaped pupils dilate and contract in response to varying light. Most advanced fishes eyes have fixed pupils.

The genus Otocinclus has at least twenty valid species to date with several more yet to be scientifically described.

A few quick notes for comparison's sake re 'other' algae eaters. The most widely sold in the west, the hillstream fish of Southeast Asia (family Gyrinocheilidae), Gyrinocheilus aymonieri, is not even close in utility compared with Otocinclus. The so-called Chinese algae eater only does a passable clean up job when small; becoming a plant (and fish) eater with age/growth. The Siamese algae eaters, genus Crossocheilus vie for first place however. We will deal with these minnow-like fishes (family Cyprinidae) in a seperate piece.

Prominent Species of Otocinclus Useful to Aquarists:

The classification, or more accurately, identification of these catfishes in the pet-fish industry is often erroneous, but should not worry the hobbyist unduly. All members of the genus are about equally hardy and industrious. To-the-species taxonomy is based on scale counts, teeth and body armor arrangement and relative body measurements. All under two inches in length.

Otocinclus affinis Steindachner 1877, the Golden Otocinclus, is probably the most commonly imported species (out of southeastern Brazil, near Rio de Janiero). It is brownish grey overall with a darker lateral body band. Not the hardiest oto, this species prefers soft, acidic water.

Otocinclus vestitus Cope, is also commonly available, coming from a wide range of streams in Peru, Brazil and Colombia. Often confused and mislabeled as O. affinus, though quite differently marked and geographically distinct.

Otocinclus flexilis Cope, the imitator or peppered suckermouth occurs in the same habitats (rivers of Brazil and Argentina) as the marbled corydoras, C. paleatus; both are similarly marbled in appearance.

O. mariae, O. vittatus, O. maculicauda, O. notatus, O. leucofrenatus and a few other "miscellaneous" otos occasionally make it into the trade intentionally or as "contaminants" with other species' shipments (often not even catfishes). Keep your eyes open for them.

Otocinclus species, the "Tiger" Otocinclus. An example of occasional offerings. These ones being spawned in good numbers in the orient for the pet-fish interest. Images shot at the 2001 Aquarama Show in Singapore.

Just a mention of the closely related genera Parotocinclus and Hypoptopoma. Though rarely imported, some of these are beautifully eye-catching, and just as suitable as Otocinclus.

Natural and Introduced Range

The loricariids are entirely freshwater and of the New World, Panama to most of South America. Waters of low elevation to more than 3,000 meters, still to swift-flowing. Otocinclus species themselves are more confined to low-lying rivers and streams of the immense Amazon basin, principally the Rio Grande do Sul and La Plata regions (so far as described).

Selection: General to Specific

Pick out initially healthy stock; this is a crucial and difficult task, and no, I have no crystal ball. Some shipments of otos are almost 100% DOA, others the opposite. Sometimes "bad" (more than 50% lost at the get go) imports suffer very little consequent loss, whereas others are all dead for no apparent reason within a few days. A few generalizations are of service:

1) Look closely at the whole batch; every individual in the place. How do they seem? Are they full bodied; that is, not skinny? Are the fins intact? Not frayed or whitish? All breathing? Alive at least? Good, go to 2).

2) Look for good color, olive brown, black and white where it should be for the species. See any with grayish white, or bloody marks, especially at the paried fin origins and belly area? If their skin is damaged, leave them all.

3) "How many do you want?" Pick out the active individuals, those cleaning up, moving around. Omit the skulking, immotile ones having "private parties" in tank corners.

4) How long have they been there? If they're going to die, they generally do so within a few days... from "ammonia" (or other metabolite poisoning), low oxygen, lack of feeding, poor handling in general. Wait for them to "plump up" and stabilize.

X) For you wholesalers, retailers who are receiving and holding these animals for a while (as opposed to transhippers, break-packers/jobbers): A) do utilize acidified water and methylene blue (for oxygen carrying ability and anti-microbial effect) in acclimation (Fenner gratuitous self-citations below). B) And make sure they're provided with some driftwood and other purposeful food. The best outfits I've seen keep some microwaved/blanched zucchini, nutirtious food blocks, and defrosted frozen bloodworms in their system at all times. C) Deworm them enmasse with medicine (hobbyists can use Tetra's medicated food for parasites) applied to the food, before sending them on.

Environmental: Conditions

Habitat

If you'll take the time to seek out and acclimate healthy otos and do nothing more than provide them with an appropriate habitat, dark spaces, live plants, and clean moving water of high oxygen tension, you will find them to be extremely hardy.

As a corollary, don't be too fastidious about scrubbing the system sterile; instead just clean the front or viewing panel(s) leaving some algal growth for your army of otos.

Otocinclus are not as nocturnal as their larger sucker mouth brethren, but do appreciate cover to get out of the light and into hiding. Ideally this would be a combination of plantings, submerged wood, and other decor.

Chemical/Physical

The otos display a wide tolerance to given standard aquarium-utilized parameters, living well in soft to hard (zip to 400+ ppm total hardness), acidic to alkaline (5.5 to 8.0) waters. They do display an objection to high concentrations of organic metabolites however. You should have no detectable ammonia, nitrite, and low nitrate (less than 10 ppm) levels. The steps to maintaining these criteria are simple; undercrowd, underfeed, properly filter, and do regular maintenance (in particular water changes) regularly. Poor water quality manifests itself in death due to apparent bacterial infection.

Temperature range is wide enough, 72-82 F. (21-27 C.). If summer temperatures peg out much higher, cut back on your lighting and increase/add aeration.

Filtration

Should be vigorous and complete; move all the water around and through the mechanical, biological plus possibly chemical filter media a good twice plus per hour. As long as it does not disturb your plants, you can't have too much water turbulence.

Additionally, weekly water changes of 25% are recommended to keep metabolites low and the system "dynamically stable" (love those oxymorons!).

Handling

Though otos are technically armored cats, they should be handled gingerly, as little as possible, and only then with fine meshed nets. Avoid touching them by hand, wiping off their protective mucus and possibly getting spined by their small but spiny dorsal and pectoral fin spines. Instead, invert the net and cats into the intended system's water and let them extricate themselves. Commercial operations do well to fashion shallow draft, rectangular nets utilizing fiberglass screen door netting for these and other similarly spiny livestock.

Behavior: Territoriality

Some loricariids are decidedly agonistic toward conspecifics, the clown "plecos" (Peckoltia), and royal types (Panaque) come to mind. Such is not the case with Otocinclus; they get along with their own, other members of the genus, in fact with most everybody. There are citations that call attention to "riding" and parasitic sucking on fish tankmates, but rarely are these recorded as being ultimately deleterious to the host. More likely this behavior is a manifestation of food deprivation, and a sign that you need to be supplementing their diet with more greens.

Introduction/Acclimation

Due their intolerance of cycling metabolites and fondness for algae these fishes should only be placed in well-established systems; ones where the plants have become firmly settled and are growing.

Otocinclus should be purchased in a group (one or two per ten gallons of system is about right functionally), being social animals, and batch-processed via a dip and quarantine procedure (Fenner, 1989,94).

Predator/Prey Relations

Most all small to medium size and aggressive fishes get along with otos. Barbs, gouramis, loaches and other bottom feeders. Larger cichlids and generally agonistic species might well be tempted to try sucking them up; for their tanks, try the larger loricariids.

Reproduction, Sexual Differentiation:

Sexing otos is not difficult, but takes a trained eye. Due to their small size, the definitive gill cover spines and pointed genital papilla of males is hard to make out. Instead look to the females; they are decidedly broader and rounder in appearance.

Due to mixed species shipments, the wannabe breeder is encouraged to purchase and stock Otocinclus in as large a grouping as practical, and provide propitious circumstances (food, habitat, water quality) for nature to take its course.

Otos are are listed by some authors as "egg scatterers" contrasting with other egg-laying loricariid genera. I side with Speice, 1987, Emmens and Axelrod, 1978, Sands, 1988 list them as breeders of adhesive eggs on rocks, glass aquarium surfaces, and broad leaved plants respectively. Baensch and Riehl in their Atlases state that pairs do a "dance", embrace and about 50 transparent to cream to yellowish green eggs are laid in an upper corner of their tank. Young hatch out in 2-4 days... they list baby brine and spinach as first foods.

Feeding/Foods/Nutrition: Types, Frequency, Amount, Wastes

Inadequate feeding/nutrition is only second to selecting decent specimens as a source of mortality with these fishes. Three key points; do not place Otocinclus in new, or overly cleaned systems, they will perish from lack of food. Secondly, you must expressly provide foodstuffs for these little suckers, (e.g. sinking pellets, greens like spinach, nori, peas) especially if keeping them in an unplanted or under-planted setting. And lastly, the "wood trick"; that is, supplying your otos with some submerged wood as a needed dietary adjunct.

Disease: Infectious, Parasitic, Nutritional, Genetic, Social

As far as being members of the South American sucker mouth catfishes go, Otocinclus are barely armored against poor water quality. This shows up in their ready susceptibility to "organic pollution". For a dearth of water changes, otherwise adequate filtration, otos die from bacterial-population-explosion "disease". Maintain high water quality.

On import, Internal worms, mainly of the gastrointestinal tract and gill flukes can be lethal. Don't trust your livestock source to have done the job on these. During quarantine, feed your new otocinclus anti-parasitic food for a good week.

The too-common infestations of ich can be quickly resolved with malachite with or without formaldehyde preparations. Be wary of utilizing salt, metal (copper) or insecticide (DTHP, Masoten, Dylox, Neguvon) medications on Otocinclus; they succumb to these treatments more readily than the apparent cause you're treating.

Close:

The miniature suckermouth catfishes of the genus Otocinclus vie with the cyprinid SAE's (siamese algae eaters) of the genus Crossocheilus for the title "world's most useful algae eaters" for planted aquariums. They are peaceful, unobtrusive, and industrious little suckers; and readily available and inexpensive.

If you intend to put them to good use, just keep in mind the four cardinal points offered here. Pick out healthy stock, keep water quality high and constant, provide a suitable habitat, and suitable food including some submerged wood.

Bibliography/Further Reading:

Baensch, Hans A. & Rudiger Riehl. 1993. Aquarium Atlas, v.2. BAENSCH, Germany. 1212pp.

Burgess, Warren E. 1989. An Atlas of Freshwater and Marine Catfishes: A Preliminary Survey of the Siluriformes. T.F.H. Publications, Inc. NJ. 784pp.

Castro, Alfred D. 1996. Algae al fresco: Exactly which algae eater really likes to chomp down on this stuff? AFM 12/96.

Davis, Chuck. 1979. Choosing suitable catfish. FAMA 6/79.

Emmens, C.W. & Herbert R. Axelrod. 1978. Catfishes, 3d ed. T.F.H. Publications, Inc., NJ. 96pp.

Evers, H.G. 1996. Der hummel-harnischwels O. gibbosus Ribiero, 1908- Ein ausser gewohnlicher wels. TI Magazin 128 Apr. 96, 24-26.

Fenner, Bob & Steve Landino. 1989. Acclimating fishes. FAMA 8/89.

Fenner, Bob. 1994. Guerrilla acclimation methods, or acclimating: My way. FAMA 10/94.

Feuer, Warren. 1995. Rating the loricariids: You have algae, but will they eat it? Aquarium Fish Magazine 10/95.

Ferraris, Carl. 1988. Basic catfish nutrition: the myth that catfish can live quite nicely on food ignored by other tankmates is simply not true. AFM 10/88.

Finley, Lee. 1993. Catfish corner: Some notes on feeding suckermouth catfishes. TFH 8/93.

Finley, Lee. 1997. Catfish corner: An overview of catfishes bred in the aquarium-part two. TFH 4/97.

Frank, Neil & Liisa Sarakontu. 1995. Algae eating cyprinids from Thailand and neighboring areas (Crossocheilus). The Aquatic Gardener 8(2):3,4/95 and AFM 4/96.

Gosline, William A. 1947. Contributions to the classification of the loricariid catfishes. Archos. Mus. Nat., Rio de Janeiro, 41:79-144.

Isbrucker, I.J.H. 1980. Classification and catalogue of the mailed Loricariidae. Verslagen en Technicsche Gegevens. No. 22. 181 pp.

Kutty, Vinny. 1993. Algae eaters. The Aquatic Gardener 6(3):5,6/93.

Nelson, Joseph S. 1994. Fishes of the World, 3d ed.. John Wiley & Sons, Inc. NY. 600pp.

Padovani, Gian. 1988. The Catfish. R/C Modeler Corp., CA. 78pp.

Regan, C. Tate. 1904. A monograph of the fishes of the family Loricariidae. Trans. Zool. Soc. London, Vol. 17:191-351.

Riehl, Rudiger & Hans A. Baensch. 1982 (sixth ed. 1996). Aquarium Atlas, v.1. MERGUS, Germany. 992pp.

Riehl, Rudiger & Hans A. Baensch. 1996. Aquarium Atlas, v.3. MERGUS, Germany. 1104pp.

Sands, David D. 1984. Loricariidae: Notes from the score of nature. TFH 10/84.

Sands, David. 1988. A Fishkeeper's Guide to South American Catfishes. Tetra Press, NJ. 117pp.

Schmidt, S. 1996. Prime breeder O. paulinus- an eater of algae with strange tastes. Aquarium (Hilversum) 66(4):100-102.

Speice, Paul. 1987. Guppies to groupers: There's a sucker born every minute (Loricariidae). FAMA 2/87.

Thomas, Scott B. 1978. Suckermouth catfishes: Nature's algae removers. FAMA 12/78.

Wheeler, Stu. 1978. When your catfish calls in sick. FAMA 3/78.

Otocinclus - ''Little Monkeys'' in the planted aquarium

Found on www.planetcatfish.com

Introduction

"The brown algae appears when the aquarium is young, is brown in color, and covers everything from walls to driftwood to leaves like a thin curtain. It is easily dealt with by adding a natural enemy, the best of which is Otocinclus."

With these words and the virtual omnipresence of Otocinclus in his fabulous planted aquaria, Takashi Amano and his seminal book, Nature Aquarium World, have helped foster a desire among aquarium plant enthusiasts to house Otocinclus in their tanks. These diminutive heroes do indeed have much to commend them. As Amano points out, they do a great job of removing certain types of algae. Moreover, they do this without damaging the most delicate of plants. They are typically inexpensive, readily available, relatively easy to care for and are certainly fun to watch. So much so, in fact, that in Southern China and Hong Kong, Otocinclus are often sold under the name "little monkeys", a moniker that aptly describes the sight of a school of these fish cavorting through the "jungle" of a densely planted aquarium.

Yet, while increasingly popular, much about these charming little fish remains poorly understood. The trade name Otocinclus, or "Oto" for short, refers not to one particular species but to several related genera, comprising about two dozen species. This article sets out to introduce Otocinclus, their place within the wider world of sucker-mouth catfish, and the knowledge necessary to give them appropriate care.

Taxonomy: Don't get technical with me!
Otocinclus are commonly known as "Otos" or "dwarf sucker-mouths". Perhaps the latter name is slightly more appropriate, as not all the species we will discuss belong to Otocinclus; but then again Oto is much shorter! Let us first define what is and what is not a dwarf sucker-mouth. To do that, we have to delve into a little science.

Virtually all aquarists know a "pleco" when they see one. Whether we are discussing the giants of the family, the striking zebra plecos, whiptails, bristlenoses or otos, we are talking about South American sucker-mouth catfishes that belong to the family Loricariidae. With more than 70 different genera and well over 600 described species (with many further species available to aquarists but still undescribed to science), it is the largest family of catfish found for sale in the pet trade by far. This huge range of species gives the aquarist a vast, yet often difficult choice in selecting suitable sucker-mouths for their tanks.

To further sub-divide this large family, scientists currently classify each genus into one of five sub-families. Firstly, we have the Hypostominae, which includes the "common pleco" (Hypostomus spp.) and the sailfin pleco (Pterygoplichthys gibbiceps). Generally these fish are omnivorous and good algae eaters, but they are even better plant eaters! Furthermore, they grow to large adult sizes and generate vast amounts of waste. Adults of these species would destroy a densely planted tank in minutes just by swimming around. Even though most specimens available in pet stores are small juveniles, they grow rapidly given reasonable care, and soon outgrow their welcome.

Next are the Ancistrinae. Recent research suggests that this family is part of the Hypostominae. In terms of husbandry it is the most varied of the sub-families. Within its ranks can be found the mid-sized Ancistrus species, commonly known as "bristlenoses", which do have a place in the planted aquarium but can be destructive as adults. The strikingly beautiful Zebra plecos (Hypancistrus zebra) are out-and-out carnivores, and are a questionable choice for the typical planted tank. Clown and Royal plecos (Peckoltia or Panaque sp.) are typically opportunistic omnivores, but certain large Panaque species will eat almost any plant matter, including, as recent scientific research shows, wood! The strong teeth developed by these fish to rasp away at submerged wood will scratch and spoil Plexiglas tanks, and they have even been know to remove silicone sealant from glass tanks!

While the Ancistrinae are among the most interesting and colorful catfish in the hobby, they are not (with the arguable exception of Ancistrus) good candidates for the typical planted aquarium. Aside from the dietary preferences, many of these species require a strong, oxygen rich current to thrive. Though you may get away with only moderate damage to plants in the short run, in the longer term, plants and / or fish are likely to suffer.

Next we have the Neoplecostimae sub-family, the members of which are the least suitable of all Loricariids for the planted aquarium. Aside from the fact they are rarely imported, they are, in the main, catfish from fast flowing, oxygen-rich, cool water that require these parameters to be replicated in the aquarium.

The sub-family Loricarinae is most commonly represented in pet stores by the whiptails or lizard cats. All members of this family are so elongate that, even for plecos, they are poor swimmers. Members of at least two readily available genera (Sturisoma and Rineloricaria) can thrive and even perform meritorious service in the planted aquarium. These fish look so bizarre, more like insects or lizards than fish, that they are almost guaranteed to stir up conversation by jaded guests who might otherwise not find anything remarkable in even a lushly planted and well-maintained aquarium.

While some of these fish grow quite large and could be difficult to accommodate in the typical home aquarium, the specimens sold in the trade usually remain at a reasonable size (5-6") even as adults. Unfortunately, other members of this sub-family (Farlowella species, for example) seem to live short lives in the aquarium. It has been speculated that even in nature they live for just a season, like killifish, but this is unlikely to be true. Some aquarists have kept them for years on end. It is more probable that they fare poorly largely because they are somewhat delicate fish that adjust poorly to the rough conditions of their capture and transport. Once settled, they require consistent, high quality water conditions.

Being shy fish, they are more likely to thrive in a well-planted tank than in a relatively bare one. While fish in the whiptail group do eat algae and generally do not damage plants, they are not voracious algae eaters. Although not schooling fish, kept in sufficiently large numbers, say 1-2 per 10 gallons, they can do a creditable job of keeping soft algae under control.

Finally, we come to the sub-family Hypoptopomatinae, within whose ranks we find our Otocinclus. The Hypoptopomatinae is a fairly small sub-family with approximately 70 species belonging to a handful of genera. All are relatively small and are typically found in small streams, and along the densely vegetated, slow moving banks of larger rivers. Superficially, all members of the sub-family look quite similar. Only a minority of these species (perhaps 15-20) are seen in the hobby, where they are generically referred to as "Otocinclus". One cannot blame hobbyists for this confused state of affairs! Even the experts are confused - or at least were until recently.

In 1980, Isbrücker separated the subfamily into two tribes, with Hypoptopoma on one side and all the others on the other. Hypoptopoma, which look like larger Otocinclus, are differentiated by having eyes in a lateral position on the sides of their heads (hence the scientific name, meaning "low eyes"), rather than towards the top, as in most other members of the subfamily (and most plecos in general).

With the publication of Scott Schaefer's revision of the genus (2), some order was restored to the systematics of the tribe to which Otocinclus belong. Unfortunately, however, hobbyists may now feel more confused than ever because of the major changes made in the old taxonomy and the highly technical criteria used in the reclassification. Ultimately this is all for the good, but it will take a while before most hobbyist literature catches up.

In essence many species formerly considered as Otocinclus have now been reassigned into the genera Microlepidogaster (the largest asylum for Otocinclus refugees), Parotocinclus, Otothyris, Pseudotothyris, and Nannoptopoma. Five very similar looking (to the aquarist) new species of Otocinclus are also introduced in the paper.

Of these genera related to Otocinclus, only Parotocinclus and the rarely available Microlepodogaster are really suitable for the slow moving, often low oxygen environment of a planted aquaria. The most commonly available species available to hobbyist is the Red Tailed Oto, Parotocinclus maculicuada. As with many a common name this one is misleading, as the fish is one of several species with red fins and isn't really an Oto. While we are on the subject of fins, Parotocinclus are differentiated from Otocinclus by the lack of an adipose fin in the latter. The adipose fin is the small fleshy fin between the dorsal (top) and caudal (tail) fin. This is entirely absent in Otocinclus. The red fin oto isn't a great algae eater, but can be housed in number with true Otocinclus in planted aquaria.

Otocinclus and the Hobbyist
To the general hobbyist, size is the primary factor that differentiates Otocinclus from these other closely related genera. Otos are the smallest Loricariids around. Given the fact that all Otos are imported, this means that they are cheaper; you get more algae eating miles out of your dollar if you buy Otos. Their small size, however, means that in order to keep a large planted tank free of algae you need a jungle full of monkeys. Fortunately this isn't a problem for our Otocinclus, who are a sociable bunch. Moreover, all species of Otocinclus commonly imported are the ones suitable for planted aquaria. The most commonly imported species are Otocinclus mariae, O. macrospilus and O. vittatus. There are others and recently the undescribed "zebra oto" has made quite an impact on it's appearance.

Otocinclus and their close relatives are widely distributed throughout the Amazon basin. Some rarer species exist in the colder, more southerly parts of Brazil and Northern Argentina, but these fish are seldom exported and you can rest assured that they will not be selling for $2 each! As with most widely distributed species, Otocinclus are adaptable. In the wild they can be found in slow moving, relatively deep water at the side of rivers. The boundary between riverbank and river is often not obvious because of the dense vegetation growing at the water / land interface. Tall reeds and grasses dominate this region, and it is the submerged part of these plants that Otocinclus call home.

When traveling the Amazonian waterways at, it is common to encounter "floating meadows", large portions of tangled vegetation that have broken loose from the riverbank and aimlessly follow the rivers languid course. Upon close inspection, these mobile green islands are full of fish and are literally teeming with Otos. Local ornamental fish collectors often use these "meadows" to source their catch as they are easier to work with their nets than the tangled shore.

Acclimatizing Otos to Planted Aquaria
We often hear that a large group of Otos has been purchased for a planted tank but the survival rate of these new introductions has been very low. Sometimes even total loss is experienced. We have developed a conditioning procedure to deal with this common problem. The key to our approach is to avoid putting the Otos directly into a planted tank. This is especially important when dealing with large aquaria. For our purposes, any aquarium with a surface area of more than three square feet is "large".

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Set up a small tank (an 18" cube is a good size, but a tank even half this size will do) with two sponge filters driven by a dual output air pump. There are several reasons for adopting this method of filtration. Firstly, since it is best to use a bare bottom tank with no substrate, under-gravel filtration is impossible. Secondly, the water should be well oxygenated but not overly turbulent. Thirdly, Otocinclus like to feed from these sponges, as well as the tank walls and base.

If you live in a cool climate and have access to a sunny window, your oto tank should be situated in front of the window. The water temperature is best kept at around 76-78°F. If you live in a warm climate, letting full sunlight fall on a small tank will not be a good idea, and conventional aquarium lighting should be used.

Water from an existing healthy fish tank should be used, or a couple of hardy fish such as guppies can serve to seed the tank. It will not take long for brown algae to appear. Your first purchase of Otocinclus should be added at this point. Since otos are a schooling fish, and many mouths make quick work of algae control, it's best to start with a school of 6 - 10 otos. Feed flake, frozen bloodworm (sparingly) and spirulina disks. We do not feed any fresh vegetable matter at this stage, because we are feeding for quick strength and health.

Unless you have a very good retailer or the Otos have been in the shop a long time, they will not be very well fed. Moreover, in a lightly stocked, well-maintained planted tank, there also won't be a great deal of food around for a school of hungry otos. The available non-vegetarian food must be shared with the tank's other denizens. By making sure your otos are well fed prior to introduction into a large tank, they are much more likely to settle in successfully. A well-fed oto should have a slightly rounded, protruding belly with an almost silver sheen to it.

Not every aquarist has problems introducing large groups of otos to a planted aquarium, and this conditioning procedure is not a prerequisite to oto survival and longevity. But if you have tried to introduce otos to your tank and been discouraged by the results, the approach outlined above is likely to improve your chances of success.

What does it take to maintain healthy Otos in the planted aquarium?
Once settled in, maintenance of these fish is quite straightforward and hassle-free. It is common for Otos to congregate in areas of water current, so don't fret over such behavior. A world of warning, though: if you have a strong filtration system, you may need to shield the inlet in such a way as to prevent your Otos from being "filtered". Love of water flow and an inquisitive nature has prematurely ended the life of many an Oto. Practice golf balls (like Ping-Pong balls but with many 6mm holes) or heater guards can be utilized in the Otos' defense.

If you are worried about the Otos not getting enough to eat, add small pieces of blanched or quick-frozen vegetables from time to time. Zucchini, cucumber, lettuce and Brussels sprouts are all good. You can buy sucker-footed clips for holding vegetables in places, or just go with the low-tech approach of fastening the vegetable to a rock with a rubber band. Just be sure to remove any uneaten vegetable matter before it spoils and degrades the tank's water quality.

Reproduction
Though not exactly common or easy, quite a few aquarists have succeeded in getting their otos to spawn. This is often the result of serendipity, rather than any conscious effort on the part of the aquarist. In large planted aquaria, the first indication that the stork has visited is simply the fact that there are more Otos now than there were a month ago! Eggs are laid in small clutches, usually in remote corners of the tank that are easily overlooked. Fortunately, the tank's other inhabitants also easily miss them; so many eggs often survive to release fry. Only after two or three weeks do the tiny fry begin to resemble the adult form, and it is typically at this stage that they become apparent to the aquarist for the first time.

Remember the small conditioning aquarium we mentioned earlier? This is also the perfect breeding tank. Given that you can actually summon the effort to remove them from the main tank, a heavily set female and at least a trio of males should be added to this environment and treated to regular water changes. Eggs are easier to spot in this scenario, and it is best to return the parents to the main tank or another similar holding tank in order for the fry to hatch unmolested. Although some breeders maintain that well-fed Otocinclus do not eat their own eggs or tiny fry, at least as many report much greater brood counts if the parents are removed.

Go get some!
We hope we have given you some new insights into the taxonomy and husbandry of these fish and have helped you avoid some of the potential misfortunes that can befall the aspiring Oto keeper. We can think of no better "utility fish" for the planted tank enthusiast and hope that our huge enthusiasm for this diminutive catfish is at least a little bit infectious!

References:
(1) Nature Aquarium World, Vol. 1 - Takashi Amano - TFH Publications
(2) The Neotropical cascudinhos: Systematics and biogeography of the Otocinclus catfishes (Siluriformes: Loricariidae), Scott A. Schaefer, Proceedings of the Academy of Natural Sciences of Philadelphia 148:1-120, 1997.