They are a really good souse of food, but they tend to spit the skins out and I have noticed they pass through the fish fairly quickly and not to well digested. Its a good snack but make sure the filters up for it if you are going to feed them a lot of them. Like most predatory fish capable of eating large quantities of food most passes through them without completely being digested I prefer worms. When I say I do mean the fish not me.