I boil up some water then throw in some frozen spinach leaves and a brussel sprout, let them cook for a couple of minutes then pour a little cold water over them after I take them out then I cut them up into small pieces. In my tank are 4 silver dollars, 2 rainbow cichlids, 3 gouramis ( 2 gold, 1 opaline) 1 large tinfoil barb, 2 plecos and 3 Blood Parrots. 15 fish in a 55 gl. tank. When I put these cut up vegetables in the tank every one of my fish, ( except the plecos) race to the spot and frantically gobble up the offering! They all seem to love spinach and brussel sprouts lol!