I have the knock off Python, I think it’s made by Aqueon. Anyhow when I change water I turn off the filter (hang on the back, powerfilter) and siphon the water out with the python. When refilling I turn the valve and let the clean water run in the sink for a minute, then fill my tank. Then I add AmQuel to remove the ammonia/chlorine in my tap water. My question is should I add the ammonia/chlorine remover before I add tap water or after? I guess I’m just afraid I’m killing the bacteria in the tank, or stressing the fish by having Chlorine in the water for a short amount of time.