my rbp's are only about 1.5 in. long, they eat exclusivly bloodworms right now. i want to start to vary their diet. i've read that every one seems to agree that feeders arent the best and and most poeple are pro fish fillets. how do i prepare the fillet, do i slice it into small peices, freeze the unused and thaw as needed. these are my first piranah nd i want to do things right.