I'm still looking for the source of the "forum created fact", but first I dithered around in my Ich journals. But I bet it comes from the studies involving propagation of Ich in the laboratory setting. Sometimes all people need is a single sentence that sounds supportive of their claims and all of a sudden that journal is their proof. The runaway sentence in the article I'm reading "A technique for the preservation of Cryptocaryon irritans at low temperatures" and one sentence reads "However, none of the strains went beyond 34 cycles of propagation..." Ich is notoriously hard to propagate. I do not think ich is self limiting.... I think they are human limiting. Does anyone have access to the Parasitology Research journal? I have a subscription, but for some reason 3 Ich article I want on the topic are available in "Preview Only". I don't know why that is.