Otocinclus catfish is small, armored algae eaters that are popular because they removes algae from your aquarium’s glass. What could be better? I mean, who wants a tank that needs to be constently scrubbed?
These fish seem like a perfect solution. They’re peaceful, live in small groups, look nice on the glass or leaves, etc. Sounds good. The arrangement is simple.
Provide some food, provide some space, and the fish will keep things clean. Everything sounds beneficial… but thing change rather quickly. In the first week, many people lose their Otos.
This behavior frustrate hobbyists because we think there’s something wrong with us. We tend to think that our fish were sick or water was poisoned. The reason is usualy simple, though easy to miss.
Disease isn’t the issue. Starvation is. And it’s because hobbyists misunderstands them.
Why Otocinclus Catfish Die and How To Save Them
The Real Reason Otocinclus Catfish Die
First, the primary cause of death for these fish are an incompatibility between what this species requires and condition of your new tank. Not only are they specialized algae grazers, but they are not detritivores. To survive, they require a mature, thick algae film.
You place them into a new tank. What do you see? The glass is clean.
The wood and rock are sterile. There is no food. Immediate hunger coupled with stress from shipping.
This is where most keeper fail. Algae takes time to build up, and there’s no way to rush the process. It can take months for a new tank to reach maturity and create biofilm for the Otocinclus catfish to consume.
A mature tank will have it. The biofilm. You’ll notice some green on your wood, but again, this isn’t sufficient nutrition for an adult-sized catfish.
The natural process is slow compared to their metabolic rate, and you’re counting on nature to work its magic. That’s hard when aquarium keeping require patience. But it requires patience here.
Feeding Otocinclus in New Tanks
Blanching some vegetable, such as spinach, zucchini, etc., then giving it to them will help. So will providing sinking pellets and/or algae wafers. These food items sustains the fish during their wait for algae.
That said, Otocinclus catfish are surface grazing animals by design. Feeding them wafers isn’t permanent. They won’t die, but wafers aren’t the same as feeding them natural algae, and they don’t provides the same nutrition.
Preventing Jumping During Acclimation
Acclimation and quarantine matter too. Also, ottos (Otocinclus catfish) jump. Under stress, they jump.
Whether from perceived danger or something surprising, these fish jumps. So what? They will jump if you acclimate them in the open in a bowl.
They jump because they’re exposed, and they don’t like it. They jump and many end up lost and dead without your knowledge. Acclimating in a covered container is critical.
Covering the container isn’t much, but that’s all it takes. It’s life saving. Lids save lives.
Stocking Density and Schooling Behavior
How many should you stock? For their own well-being, stocking density matter. Otocinclus catfish are social and schooling.
Their behavior is most natural when there’s a school of them. They feel safe in numbers. Keeping a single specimen will not only be stressful but also unhealthy.
Six or more make the best choice. In a group, they feels secure enough to forage and eat. When left alone, it hides and eventually dies from starvation.
Unfortunately, hobbyists view otocinclus as solitary pet. They’re not. They are social animals.
Make sure to keep them in a social setting. That’ll reduce their stress and increase their appetite. Grazing is part of the tank’s environment.
Creating a Suitable Environment
There isn’t much food on smooth surfaces such as glass or polished rock. Biofilm grows well on rough surfaces such as Anubias leaves, Java Fern, and driftwood. Providing these types of surfaces allows the fish to feed where they would in nature.
It also provides them with places to hide from view, reducing their anxiety. Grazers won’t be content in an empty tank. Provide them with a landscape that facilitates their behavior.
Complex hardscape and live plants is essential for this purpose. What you have is a livable environment instead of an empty box. Otocinclus are not cleaning machines, but live animals.
They are not objects for your pleasure. To keep an otocinclus alive, you must shift your mindset from decoration to husbandry. It has its own biology which clash with the look of a pristene new fish tank.
Accept that a little bit of algae is healthy; not unhealthy. Feed it supplements during the growth of the biofilm. Keep the lid closed.
If you match the tank environment to their instinctive behaviors, they’ll thrive. They’ll breed, grow, and clear the glass. The trick: they should of had food to eat first.
