Well, he could be referring to time. I know some people actually "age" their water in order to get rid of all of the nasty stuff. Some people use RO water too. I'm not really familiar with either of these methods, so I couldn't help you with that.
I personally like Seachem's Prime. Takes out Chlorine/Chloramines/Heavy Metals, detoxifies ammonia/nitrite/nitrate. The stuff is also extremey extremely concentrated. You use about 1 ml/10 gallons of water :