Good topic... I just go from my tap to my tank with an adaptor and a hose.. However I've always added the conditioner after I add the water, but my last change my fish looked pretty affected after a 60% water change.. So I desided to add the conditioner BEFORE I Added the new water (after I removed 40%)... Is that suitable? I know on the bottle it says add with new water , but if I add after removing but before added new , does that works just the same?? Thx!