#airhaven

Step 1: Feed them!

The most important step. Get them eating Repashy Soilent Green. Otos that are eating a nutritious diet are incredibly hardy. You too can learn to expect zero losses in new groups of otos.

They’re wild-caught, so they need to learn to recognize their new food. Two ways to teach new otos quickly:

A) Start them in a cycled bare-bottom quarantine tank. No lights (at least initially), with driftwood or something to hide behind. The lack of substrate and other distractions helps them happen upon food (they’ll try to eat all kinds of random crap off smooth surfaces). You can offer blanched spinach to keep them from starving before they take to the staple food. The floor will be littered with SO MUCH poop once they’re eating properly.

Or, if you aren’t buying your otos all at once…

B) Put them in a tank with an established group. They’ll take to prepared foods in no time if they see other otos eating it. Quarantine is important for avoiding disasters, buuut… sometimes it’s in the otos’ best interest to be placed with established feeders in a comfortable environment asap. Examine your new otos very carefully for signs of disease before trying this. Attempt at your own risk.

(Moving established eaters to the quarantine tank is another approach, but this tends to upset my established otos to the point that they don’t eat reliably and become poor teachers. They do not appreciate the change in environment.)

You can also feed them other blanched veggies like zucchini, but I’ve never kept them on a veggie-only diet. Try to think of them not like herbivores, but as scavengers with a preference for plant matter. (They’re aufwuchs eaters, specifically.) I find that they have a pretty large overlap with my RCS in terms of food/grazing preferences. They’ll go nuts for Shrimp Souffle if you want to get that for your shrimp.

Note that Otocinclus have spiraled intestines. If you can see this spiral on their bellies, your otos are well-fed. If you can only see plates or what look like ribs, then they are not getting enough to eat.

Step 2: Shoal size

The larger the shoal, the more comfortable they feel. Absolute minimum is ideally around 10. Again, they are wild-caught, so they know what a natural shoal is like. They know what it’s like to be surrounded by hundreds to thousands of other otos. You can sustain a buttload of otos if you’re feeding Repashy instead of trying to cultivate algae for them.

Step 3: Environment

Maximize surface area with lots of plants and driftwood. They like to have lots of places to perch and feel hidden. All these surfaces will also host biofilm for otos (and shrimp) to graze on.

They seem to resent having tank lights, but this is necessary for the plants. If you want to, you can counteract this by having floating plants to dim the light. You can also stain the water with tannins using Indian almond leaves or oak leaves. Leaves also = more surface area and material for grazing. For a more dramatic solution, you can keep your plants crazily overgrown. You can also just create a dark area in the tank for them to retreat to when the lights are on and they find themselves dissatisfied with your choices. You may often see them come out to do a joyful dance on the front glass once the stupid light turns off for the night.