Tearing the tank apart is a metaphor for "trying like hell to catch all the little fishies but knowing I'll gave to remove 90% of the aquascape to be successful."
This is my experience with catching all the fish and QT'ing them. Also, you run the risk of cycling the QT, blah, blah, blah. So I guess it boils down to whether you want to go through all that, and then use a QT before introduction forever and ever. Or keep a close eye on it by counting dots/fish, improving water quality through a good sized water change, and feeding enough to keep the fish well-fed.
Now to the nerdy stuff for Matt:
A protein modulated immune response is not what is described in the literature. Fish up-regulate genes when they are exposed to trophonts (parasitic stage) one article included 21 genes, some of which were inflammatory, others proteins, and others involved with kidney and liver function. Cited below.
Mohd-Shaharuddin, N., Mohd-Adnan, A., Kua, B., & Nathan, S. (2013). Expression profile of immune-related genes in Lates calcariferinfected by Cryptocaryon irritans. Fish & Shellfish Immunology, 34(3), 762-769.
This advances the last point, showing that fish can elicit an immune response when INJECTED with heat-killed c. irritans, showing that the immune response is not contained to the integumentary system. cited below
Dan, X., Zhang, T., Li, Y., & Li, A. (2013). Immune responses and immune-related gene expression profile in orange-spotted grouper after immunization with Cryptocaryon irritans vaccine. Fish & Shellfish Immunology, 34(3), 885-891. doi:10.1016/j.fsi.2012.12.011
So what is responsible for the immune response? The following article concludes that several compounds from the eicosanoid pathways are prevalent: such as IL-8 (inflammatory), COX-2 (inflammatory), and a lectin (binds to c. irritans to signal for destruction). cited below.
LI, Y. W., DAN, X. M., ZHANG, T. W., LUO, X. C., & LI, A. X. (2011). Immune-related genes expression profile in orange-spotted grouper during exposure to Cryptocaryon irritans. Parasite Immunology, 33(12), 679-987. doi:10.1111/j.1365-3024.2011.01337.x
Or perhaps it is a serum protein which has anti-parasitic properties? This seems to be the case with rabbitfish. Cited below.
Wang, F., Xie, M., & Li, A. (2010). A novel protein isolated from the serum of rabbitfish (Siganus oramin) is lethal to Cryptocaryon irritans. Fish & Shellfish Immunology, 29(1), 32-41. doi:10.1016/j.fsi.2010.01.006
Plus, the immune response of the fish is dose-dependent on the number of trophonts. This means that a fish might not get sick if a few are around, but more than likely will when a bunch of them are around. Nor is the mortality rate anywhere near 100% at realistic doses. The variability of mortality is likely due to fish health (water quality, and feeding in our discussion above)
Mattews, R. A., & Burgess, P. J. (1995). <em>Cryptocaryon irritans</em> (Ciliophora): primary infection in thick-lipped mullet, <em>Chelon labrosus</em> (Risso). Journal Of Fish Diseases, 18(4), 329-335.
So what does it all mean? These articles show that no fish in the wild are "ich-free", and that infection is dose-dependent. The immune response is not restricted to a protein in the slime coat, but is extensive, involving all the inflammatory responses you would expect, antibodies, and even novel parasite-destroying serum proteins. And the variability in response suggest that fish health and prior exposure play a huge role. There are even immunizations for fish with heat-killed c. irritans, proving that a long term immunity is the reality, and not temporary. The take away message is that your fish can indeed mount an effective immune response, and this can be cultivated by good husbandry (∆h20). This immune response will KILL parasites in the future and disrupt their life cycle... this is also the obvious mechanism for prey-parasite equilibrium in the wild.
I like science... a lot.
