Mine do well with frozen foods, formula 1 & 2. I have to place it by their mouths and hold it for a second, they are not sticky so it will float away. The guy I bought mine from was feeding it something similar, he had lots of babies and needed to thin them out. Some of the brighter colored ones are very expensive as stated, mine are florecent green and purple hairy mushrooms..not the prettiest but I love them. You will love mushrooms, they really make up a tank..I just got a neon blue one from the same person..he's so cute. When you first get them they will look aweful, slimy looking but in a few days they really put on a show. They produce a little slime but nothing to worry about. That is my experience with them, I haven't had them very long and there are others on here that can tell you more. Good luck and you won't be sorry.