will Hypo salinity kill all the inverts in my tank ?

[Pegasus]

If it were me I would not worry too much unless the fish were visibly sick ie. breathing rapidly, hiding in the corner all day, not feeding, etc.

trilinearmipmap

Saltwater ich is actually a parasite and not a viral infection. It has it's own live cycle and the intent is to disrupt the life cycle. Without treatment, the parsite will continue to reproduce increasing its own population. Since this parasite resides on/within the substrate, water column and on the fish at varius stages of it's life, it is considered contagious and will spread to the other fish in your tank. The fish is sick when you first notice them. If you wait for the symptoms you mention, it is probably to late, as the fish will be infested with the parasite and the time line to wait for the unhatched parasites to hatch and then be irraticated may be to lengthy for the fish's survival. My experience has shown that when treating an infected fish in your reef tank, it takes about two weeks to irraticate using the reef safe medications. It is highly recommended that it be taken seriously right off at the begining, as it is probably the number one cause of losses.

This link is added for your reading pleasure:

http://www.wetwebmedia.com/ichartmar.htm

Larry