I bought an Aqueon circulation pump the 500 version. I was never really happy with it, but it's what the pet store had at the time. One thing I noticed right off the bat is that it's a suction cup instead of a magnet...ok :/. I was fine with it as long as the suction was powerful. It was not the cup barley wanted to attach. So I went and hunted for the reciept and kept it and the box incase the suction cup ever failed. Which I assumed it would because the suction was so horrible it barley wanted to stay in place. But it's lasted me a month or so maybe more. Then today when I was doing a water change I had to readjust the pumps head and the thing just broke like nothing. The part that attaches to the suction cup must have been weak or something because it just came off . I'm not sure if the plastic was bad or what but sofar this product has been kind of a pain in my butt and I'm going to return it either for a replacement or see if I can get a refund and try and buy a nicer magnet power head.