Introduced 3 Zebras to a new tank. 2 died apparently from ech. Treated the tank and the third Zebra doing well. How long should I wait before adding new fish. Tested the water and everything looks good.
If you are certain ich was the issue, it is advisable to continue treatment for two weeks. You don't mention the treatment method, but increasing temperature helps (it speeds up the ich cycle) and can even kill ich outright at 86F (30 C) for two weeks.