After treating my tank with greenex (following the directions) my flame angle and blue tang died. I have done one large water change (55%) per the directions on the greenex. How long do ya'll think I should wait until I add more fish? I am running carbon in my wet/dry right now to help remove some of the greenex. Also I still have two black perculas in the tank that are doing great and never did get the ich that the other two had.