TOOFLY. I have been using that ATO for almost a year now and I am very happy with it. The cheapest I've seen it is $79.99 (usually goes for $99.99). It has dual float valves and also has a fail safe circuit that won't let the unit run for more than 3.5 minutes. All you need to add is the pump and tubing. Sets up very easily. Whichever direction you go in, I highly recommend some type of ATO as it is one less thing to think about with maintaining the reef. Good luck with this and let us know what yopu ended up doing.