Can ich live on corals/frags?

Fact is, you can only rid your system of the active parasites. Once the cysts are released from a fish, they have a very short life span without a fish host.

If you follow the link I provided, you will find that the majority of wild-caught fish (and the majority of fish we buy are wild-caught, btw) have the ich parasite lying dormant in their gills where it can live indefinitely. If that fish becomes stressed, then the parasites will release the cysts to start a new cycle of feeding and reproducing.

 

So the fact is that quarantine may not actually prevent ich from ever coming into the system?

 

Short answer is no. However, it does give the fish a chance to calm down and you the opportunity to ensure that it doesn't become infected from the stress of being caught and transported about.

 

Makes me want to put all the fish back in the tank that is fallow...

 

OK, that makes sense.

Thank you, Trent... I always enjoy learning something new.

 

Sorry if I wasn't clear enough... You NEED to allow the tank to sit without any fish to kill off the active parasites. The one's that are dormant in the fish's gills are harmless as long as the fish doesn't become stressed enough to wake them.

 

Just to clarify, a new arrival should be quarantined and observed, if ich is noticed it should be treated since it is active?

 

Yes, absolutely.

 

I think you have your answer already from what Dingo and Mr. Bill are discussing. From what I take from they are saying, ICH will always be in your system. Now ICH won't be a problem as long as your system is healthy and your fish aren't stressed. That is my take on this.