That's great Barb, let us know when you try the fish emulsion. I've run into a few threads on some other tropical forums where folks are using the Rid-X stuff to cycle. I was only joking about that! I'll search some more and see if I can find some more convincing data. Right now it's just a few snips about " I know a guy that cycles with Rid-X", but no hard data or methodology. I guess the first thing would be to read the list of ingredients. I don't think it would have the ammo, but maybe it would be useful to speed the nitrite part of the cycle.