I have a 2" ClownKnife, some 5" RedHookSilverDollars, a 3.5" Senegal Bichir and a 3" Oscar. I am also planning on getting one or two small Dats soon. I have heard great things about HikariMassivore, but I thought my fish were too small to eat it. Am I right? Can I, or can't I?