| I have one python that services all of my tanks. Anytime I've had some fish with ich, I just did that tank last. It's never spread to the other tanks. Ich is often a reflection of water quality and overall health of the fish (not all fish are created equal). Does every fish have it or just specific ones? If every fish or a majority of the fish are sick, then it's probably due to the water. HOwever, if only a few fish have it, it could be that they are just generally weak fish. I think overbreeding has had a hand in the matter. Also, some species are more suceptible to it than others. |