It’s cold in Chicago and it is not going to be warming up any time soon. I have my controller set to kick a heater on at 79*F. In the summer, it’s perfect. Temperature doesn’t drop below 79*F, and over the course of the day, it usually hits 82.5 – 83*F. Now that the house is cold, My heater has been having trouble keeping up with my normal tank temperature. I added an extra heater, which certainly helps, but uses more electricity to keep up – as if my winter heating and electric bills aren’t high enough…! Fortunately, the Aquacontroller has a solution to this problem….

Graph below shows my daily temperature swings as of late. One night down to 73*F from 79*F at the end of the day. Yes, many reefs see daily temperature swings above and beyond this, but I’m not comfortable with 7* swings in an aquarium on a regular basis. I think 4*F daily swing is perfect for a reef tank.

The Ac3 is capable of water temperature according to a set of coordinates. The ‘season table’ sets sun and moon rise / set for each month, and adjusts water temperature accordingly. I’ve set mine for Apo Reef in the Philippines. According to the season table, December should be ~76.0*F on average. By the end of January, the water temperature will have drifted down to an average of 75*F, ramping back up to 76 by the end of February. By mid-June, the average temp will be 78, heading up to +80 in July.I think this is a great feature which still allows for my daily swings of 4*F once the halide comes on, but it takes some work away from the heaters during these cold Chicago winters.