Ich

[lmforbis]

My understanding is humble fish' timing came from some recent articles that have identified strains of ich that need the full 76 days to die off. These are just his calculations based on the data in the paper. I haven't been able to find that link.
Obviously, as we know, the best way is to prevent it from getting in in the first place. Unfortunately few hobbiests start out that way and end up with some sort of disease before they understand the benefit of proper QT.

 

[beth]

Yes, literature has been out there for 15-20 yrs about "strains" that are resistant to standard procedure. In terms of ich in hobby fish (living in captivity), parasites and other disease-causing organism can develop resistance resulting from improper, unsuccessful treatments--not employing proper treatment course which does not kill the source of the disease. These sources then become resistant (whether parasite or bacterial infection) to the treatment. A lot of resistant strains can be attributed to the LFS that dose their displays with copper just enough so that parasites don't show up on fish they are selling, but not really doing a proper QT course.

However, I have not really kept up on the latest literature to see how widespread resistant strains are. And I agree with you the best advice to hobbyists is an ounce of prevent. Makes for a much better hobby experience.