The fish reaction say it worth the try. Mine was really skittish when I just got him so I gave him some feeder and his eyes gone from light yellow to bright red then he started eating a lot more. give them feeder once in a while can keep them more active, especially with fish that are skittish around everything. And there are fish(not FH) that if you don't give them feeders(not the crap feeder fish at petsmart or any fish stores) they will most likely not growing right.