I've tried algae wafers, sinking wafers, cucumber, squash, spinach, chard, lettuce, peas, seaweed and zucchini. The only thing they've ever eaten other than the diatoms and aufwuchs in the tank is zucchini. I have no idea why they're so fond of it. I'm willing to bet they'd go after the Repashy gel food as well, but I've never tried it; I have a great pig of a gourami who tends to selfishly devour anything that's left just sitting in the tank. It even goes after the zucchini after it softens up a bit (the angelfish do too).
Ha. You have got me beat! Sounds like sticking with zucchini is my best bet until he figures out that big thing in the tank is edible.
On the topic of catfish in general, I know my Cory catfish have long seemed to act almost blind in daylight. I obviously do not know this for fact but he acts like it when I see him searching for food right next to his head that he should be able to see but until his mouth hits it is when he acts like he has first found it.
Does anyone know whether blindness is a common theme with catfish? Just a random theory.
Other fish see food, zero in on it and attack it or swim to it.
Cory's seem to be "sniffing" the bottom and it is right next to their heads but until they finally touch it...they act like they don't see it.
Wondering if I'm correct and if maybe a common trait with all catfish? Otto's included? ( while we're talking about Otto's eating )
If so it would explain maybe not investigating new things clipped on the walls right away?,idk...maybe a stretch.