Otocinclus problems.

They aren't the most active fish, spend most of their time resting actually. That being said I've found that only about half the ottos I get at Petsmart will live longer than a month, those that survive do well. They certainly do like company though as long as there is enough for them all to eat.

Otos are schooling fish, and they should feel safer with more of them in the tank. Also, Otos in general are pretty delicate fish/ It is good you were careful with acclimating him!

i have 3 myself and they dont do much when the tank lights are on, sometime theyre out
sometimes theyre not. at night though is when theyre the most active for me, all 3 play
against the glass together dancing around and chasing each other.

Thanks for the information guys!

I purchased 8 ottos, 6 of which I put in my 150, 2 in a 27. The 6 were nothing but active, playful and non-stop grazing and flying around. The 2 were so lethargic I decided to move them with the others and they quickly became really active.

I have several theories but no answers. I believe it is either the large numbers or perhaps the increase in water flow.

I have three adults in a 15 gallon shrimp tank. Not much water flow, dim lighting blocked out by floaters and ricca and mine are breeding. The only food in the tank is a small amount of algae and shrimp food.

I also have a small school in my 125 gallon with bright lights and high water flow, considerably more algae and more flake food. They are active in both tanks but don't seem to be breeding in the big tank.

Make sure they have company with each other and they should be okay