I was wondering if anyone "over here" had tried the DIY Hydra controllers. I have made two of them and am very satisfied with them. I'm only using mine to monitor temp and turn fans and lights off and on to keep the heat down. I'll probably connect heaters in the winter if I think I need heaters. I also have a pH probe in the calcium reactor and it keeps the pH constant +- .01. You have to be a little geeky to set it up as you program it in C. It's basically a knock off of an Arduino.