Otocinclus, the Wonder Cat!

The most common nuisance in a typical aquarium is the ever-abundant fiend known as algae. It can grow on your plants blocking light and restricting growth. It can grow on glass and block the view of the world you have created. In short, find a surface and it will grow! Short of periodically scrubbing every inch of your aquarium, or not allowing a single glimmer of light into your tank, what can be done to ward off this tormentor? Meet your best friend and aquatic lawnmower: the Otocinclus.

The Otocinclus is a dwarf sucker-mouth catfish that only grows to be about 2 inches long. The Otocinclus is a tiny, lovable catfish that loves to eat algae from your aquarium, glass, and other decor. They are not known for eating aquatic plants. They are experts at eating soft green algae. This algae can often be difficult to see without looking very closely. The otocinclus can eat it before it grows out of control. The best part is that they are generally priced reasonably for what they do: usually anywhere from $1.99 to $5.99 per unit.

This little gem should be kept in peaceful tanks. Otocinclus are very healthy and can be kept with fry or even tiny dwarf shrimp. They do best when they have the opportunity to school with their own species. They will often travel in packs when they are stressed and go foraging for food. This behavior is most often seen when they are first introduced to their tank. They will stop feeling threatened once they are settled in and they will be less likely to school.

Experienced aquarists will tell you that Otocinclus are a very resilient fish. They don’t often contract common illnesses that plague other fish. Their greatest weakness is not getting enough to eat during handling.

Unfortunately, Otocinclus are not spawned in aquariums very often. Wild caught specimens will usually be what you get from your pet shop. As with other wild caught sucker-mouth catfish, this makes for a perfect storm. Otocinclus can be collected by the hundreds and taken to a warehouse, where they will remain for a few more days before being shipped out. They arrive at a wholesaler where a few hundred of them are put into a bare-bottom aquarium with no decoration and poor lighting. This means virtually no algae is grown in the tank. Algae wafers can be purchased, but the sheer amount of Otocinclus makes it difficult to properly feed them. A week or so later, they should be on their way to your local pet store. They are placed in a tank and fed by the pet shop. It is not easy to feed them, though, since most pet shops have a few dozen more Otocinclus. It is strange because they don’t have nearly as many plecostomus in one tank.

Don’t worry – even through all that stress, Otocinclus can still thrive in your aquarium. These are some simple tips to increase your pet’s survival rate.

First, make sure you have algae in the tank for them to pig out on when you get them home. After a couple weeks of poor feeding, they’re plenty hungry! This can be achieved by placing them in a quarantine tank. Once they are hungry, you can turn the light off for about a week and then watch as algae grows.

Next, buy these fish the day after they come in to your pet store. This goes against conventional wisdom which says that you want to buy a fish that has been at the pet store longer to prove their longevity and lessen the shock of being transported too soon after arrival. Given that Otocinclus are typically grouped together in such abundant numbers – and are often put into tanks that can’t produce algae as fast as they can consume it – you want the stronger fish separated from the rest as soon as possible. Sometimes it is difficult to determine which fish have been around for the longest. It is important to take your Otocinclus back home, and to acclimate them in your quarantine aquarium that has been growing algae for the anticipation of their arrival. You’ll be able to reduce the amount of time they are starving since you already have a meal ready for them at home.

Otocinclus are best suited for peaceful community setups. Because of their small size and timid nature they are easy to outcompete for food. Make sure you have algae for them to eat before adding them to your aquarium and you’ll be amazed at the algae-control one little fish can provide. Give this dwarf catfish a try and it’ll surely win you over. I know I couldn’t live without them!