When you say "fallow" . . . . ?

[auduncan]

If a fish with ich is removed from the display tank, and others remain in the tank with no signs of ich for 6 weeks, is the ich most likely gone?

[Steven Pro]

Only if you can be 100% sure that the other fish have developed a total and complete immunity to the parasite. If they only have a partial immunity, then it is possible the infestation could continue but in small enough numbers that you don't notice.

The only way to be sure is to remove and treat all the fish.

[auduncan]

I was afraid you would say that! Sounds like there is no way to be 100% sure just by visible signs.

[Steven Pro]

Originally posted by auduncan
I was afraid you would say that! Sounds like there is no way to be 100% sure just by visible signs.

Bingo!