I know that but what I am talking about is if you to many WC then you are taking all the amonia, nitrite, and nitrate out of the fishes enviroment which is a good thing but you are eventually going to starve your BB and the colonies are going to shrink and possibly deplete. Then if you miss your WC the amonia will build up and could be harmful to your beloved fishy. It may have an effect it may not. Also if you have bio media in your filter such as Bio Max the pores in it will get clogged with dead bacteria and will have to be cleaned out. I dont think 50% a day will have a real dramatic affect on a tanks balance but it will have some affect.