my personal opinion of the ECO-Aqualizer, (having actual experience with it) is that it's CRAP. glad it was free to try it. it's funny, when I called their customer service line to let them know I was returning it, (of course the guy had to try to back up it's claim) he said that it wasn't meant to help keep nitrates down, yet they claim it will reduce water changes dramatically. so I said well that's the whole point of a water change, is to keep the nitrates down (besides replenishing trace elements) he claims that it's okay to have your nitrates at 140ppm as long as it’s not a reef tank. lol. anyone here agree with that? I also didn't notice any difference in my water being clearer which is a big thing they claim it will do is give you "crystal clear water".