blitztidus
Spirited Away
That means add a little more food, or try giving them specialized food. I would also reccomend to change their diet almost daily, to give their life a little pizzaz. Like one day you feed them pellets, the next day it is frozen bloodworms, the next is flakes and so on and so forth. By the way, if you feed them flakes they will be able to eat them faster and would be able to spread out further than just float at the top or go down all in one area. 