can you really do to much waterchanges?

[Ruth]

In my 12g and 24g Nano's I change at least 50% of the water weekly - sometimes up to 75%. I don't skim these tanks and feel I need to do this for water quality. I also have sponges in these tanks which tend to be nitrate factories so they get well rinsed at the same time. As has been said your bacteria live on surfaces and not in the water column. I just make sure that my temperature, PH, and salinity are all the same for the change water as the water in my tank .