Changing out Sand. Good idea or not ..

[Aquattro]

I switched out my sand after a year for the same reasons. No problems at all. My tank is a 180, so I did it in portions to not remove the entire bacterial population.
The whole H2S thing is blown out of proportion too much. Unless you have a deep sand bed (4+ inches), I wouldn't worry about that.

I used the http://www.jlaquatics.com/product/cs...-+30+lbs..html
which is still fine enough for the wrasses and goby, but doesn't float around the tank.