I tried everything, flake, discs, hair algae everything.... that was when he was in QT
. After 3 weeks he was noticeably thin, so I ended QT
early and put him in the display tank.
After a day or so, I put the very same stuff (Ocean Nutrition Seaweed Selects) on a clip half way up the side of the tank. Within minutes he tore into it. Since then he has eaten that every day, and I now see him grazing algae all over the place.
My lesson. Don't give up.
(of course the bugger won't eat the hair algae, but that's another battle)