Bumping an old thread, but bumblefoot has been absolute hell for us. I'm not even sure I can get tricide neo in NZ. Why the distilled water? Surely that advice is just for fish since fish are harmed by chlorine? Or is the powder reactive?
City water is treated with chemicals and chlorine, and may contain trace minerals. Whereas distilled water has all the impurities removed. The tricide neo might somehow be effected by the chemicals or minerals in city water, perhaps changing its compostion. You can try using the trineo from your water source, let us know how it turns out.