A dozen bluegill managed to acquire Ich in my 75 gal aquarium. If I were to release them into my 1/4 acre pond, would they be liberated from the parasite once its cycle ends? Could the affected bluegill spread Ich to the other fish in the pond? Will Ich survive in the pond long enough to infect other fish? If so, would it be lethal considering that spring's moving in??? A small bass is also present within the tank but doesn't seem affected...are LMB more resistent?
Thanks.

Welcome aboard r.13.

Someone will chime in with more information.

Sometimes, fish get more susceptible to sickness/infections when they are stressed. How big are the bluegill? Maybe they are overcrowded. Are there other fish in there besides the dozen bluegill and the single bass?

Also, water quality might be at issue.

Raptor - Sunil is right. This parasite pops up often in an aquarium because fish are more likely to be stressed there. Crowding, water quality (like build-up of nitrogen products), etc., all cause the fish in tanks to be more likely to become infected.

http://freshaquarium.about.com/cs/disease/p/ich.htm

It is a natural parasite, and exists naturally in the wild. More information is available from the Southern Regional Aquaculture Center. Go to their web page below, and click on their publication number 476 (white spot disease).

http://srac.tamu.edu/fulllist.cfm