Why not Hypo indefinitely??

[manowar669]

I've been reading about hypo as a cure for marine ich, and I'm going through this now (had new intro in copper sulfate for 2 weeks, seemed fine, 1 week or so after introduction to display tank ich appeared on fins, now all fish are getting the hypo treatment, display tank fallow for 6 weeks, ugh!!).

Things I've read say hypo is less stressful on the fish than seawater, and of course, kills the ich. Could you keep fish (for FO tanks) at 1.010 indefinitely?

[Amphiprion]

You could theoretically do that, however, no one has done any research on the histological effects of leaving reef fish at that salinity indefinitely. Some speculate liver damage may result as there is a great shift in the sort of reactions needed to maintain osmotic balance. It is because of this that I cannot recommend it. Beyond that, it encourages the development of resistant forms of ich, bacteria, etc. that would normally not survive the standard treatment.