my oto's started doing the same when my tank didn't have enough algae anymore for them to feed on. after i bought them some catfish food which they could eat the behavior stopped completely

so my guess is that they don't have enough food and start eating the slime from other fish

just as you said it i run accros sodalis in the image part of the site and i think you are right

thank you very much for the help! and i will go back to the store to say that they mislabled their fish

here is a foto of the corydoras i need to get identified:



what is the latin name of this fish?

tnx in advance!