I DO WATER CHANGES!!!!....as stated in a post earlier in this thread........it amazes me how those of you who don't use a product can state how well it does or doesn't work. I use this product(see earlier post), therefore, according to this thread, I am either inexperienced (in the hobby for 7 years), lazy (I am physically disabled,shouldn't I be offended by being called this?) or time constrained (I am physically disabled, plenty of time on my hands). Also, because I use this product I should re-evaluate being in the hobby.......man.........this forum is just over-flowing with helpful, unbiased, friendly advice......I would reccomend to all readers of this forum, unless the chemical you are using is the almighty Prime, don't mention it!!!!!! You will be told you are wasting your money and time and shouldn't be in the hobby.