I'm one of the few "water change fanatics". I have several 55 and 60 gallon tanks and remove and replace roughly 60 percent of the water in them every week. The key to this hobby is a pure, steady, water chemistry. The longer water stays in the tank, the more it changes chemically. If you change out a lot of water and do it frequently, there's no chance of pollutants to build up before you remove them, so the fish and plants stay healthy. If you're skeptical, fill a glass with water and leave it out for a day or two. Taste it and then fill another with fresh water and taste it. I'll bet the fresh water tastes better. Believe me, the fish notice it too.
It's all about the water.
"Fear not my child, just change the tank water."