We generally just use it in the water, that way we know that they are being treated properly. I tryed it once in the beef heart but as the greadier ones eat more, so they get more of the prazi than others. It didn't cause any problems, but you don't know if each fish has got the right dosage. Also some people say to mix the prazi with vodka. Dont, I have heard some bad things about this, or if you do then you drink the vodka, and give the fish the prazi. I use the end of a 6inch rolling pin to grind the tablets up in an egg cup, then when it is a fine powder I half fill the egg cup with tank water, mix then add to the tank.