You should not top of with anything but fresh RO water. When the water evaporates out of the tank, the water is the only thing that is removed. Salt, metals, etc. say in the tank. If you top off with tap water, there will be a gradual increase in all of the bad stuff that you don't want, and would likely slowly poison your tank.
Doing water changes with tap water isn't the greatest thing, but you are removing a certain amount of impurities, and replacing them. Topping off with tap water increases the impurities.
I'm not an expert, so if this is wrong someone correct me. But it seems logical.
Doing water changes with tap water isn't the greatest thing, but you are removing a certain amount of impurities, and replacing them. Topping off with tap water increases the impurities.
I'm not an expert, so if this is wrong someone correct me. But it seems logical.