I recently saw in a Tetra brochure the presentation of a product named Tetra Easy Balance. This product claims that it has the ability to absorb phosphates, neutralize minerals etc., and - most importantly - completely neutralize nitrates, which are the main reason for doing water changes. So the period between water changes extends - according to Tetra - to an awesome 6 months!!!, which I find very hard to believe. I would like to know your opinions on this one.