This may be true but any literature I've ever read says NOT to filter your water in this manner. I can't remember why but I remember reading it quite a few times. I think the filters remove some things you want in the water. Worth checking into.
Also, this method would take me hours to do a water change. Most filter systems of this nature are awefully slow. I need 40 - 50 gallons for each water change in my 180. Weekly or bi-weekly. I don't have the patience for that.
Small bit of de-chlorinator is cheap and fast, also has stress-coat which relaxes the fishies as the new water goes in. (so they say)