I know about QT. I QT all my fish but is it nessessary to QT corals? If not can ick get into your main tank by corals? I know ick cant effect them but can ick attach to them then release themselves into the tank?
All of your fish already have Ich, but its just not obvoius because it only becomes apparent when they get stressed out or sick, then the parasite over takes the fishes immune system and starts to multiply thats when it becomes evident on the fish them selfs.
Yes, corals can carry ich into a tank, if the coral has been in a fish tank where ich is present.
I think most sellers house corals in fishless tanks, however, so it is not that much of an issue.
QTing corals becomes more of an issue due to water quality as well as lighting needs.