Hypo salinity 2 questions

[tmz]

I have used qt with copper treatment as neede for a couple of years. I am changing my qt protocol to hyposalinity . My questions are:

Can copper sulfate(Sea cure) be used in hypo if the hypo is ineffective? If not is there a minimal salinity level for it's use and why is it unwise to use it at 1.09sg?

What techniques are best for reacclimating fish to normal salinity levels before placement in the display? How long a period of time is needed to go from 1.09 to 1.025?

[JHemdal]

Tom,

I was running a search on hyposalinity for a project I'm working on and saw this post. It looks like its been up for a couple of weeks with no answer - or am I just missing something?

In any event, the other hypo thread going has advice about not using copper and hypo concurrently.

Regarding returning from hypo to normal salinity - people sometimes get this wrong. Believe it or not, you can go down in salinity virtually instantly, but the return must be done extremely slowly. I've seen people write that they lower their salinity over "a week's time". This is too long if the fish have an active Cryptocaryon infection. You can drop the salinity within 24 hours in every case (although I do not recommend that people go quite as low as a specific gravity of 1.009)
Raising the salinity must be done over a period of days or even weeks. The fish's osmoregulatory system needs time to adapt to the more saline water. Signs of going too fast are fish that suddenly look really thin - they literally are dehydrating. I typically raise the salinity by performing partial water changes with normal salinity make-up water.

Jay Hemdal

[sundancer]

I have read somehwere that the reason copper should not be used in hypo is that the lower salinity level makes copper more difficult to test and maintain steady.

[tmz]

Thanks for the replies.