the mention of Hydor brand also reminds me what I've seen today finally for the first time. I know they've been out a while, because I saw one on a board somewhere a while ago, but I just ran across the first remote thermostat that can easily be used to run under-tank heaters, these Hydor all-on or all-off heaters as mentioned above, the little wal-mart heaters that are also all-on or all-off etc! it's the Hydor Thermostat controller from www.marinedepot.com
This allows you to heat your system based on ambient room temps, not some timer setting made regardless of the systems true temp. Based on this alone, I may get to work on the atto sps reef now that I've put off due to heating issues. Circulation will be ceramic mixing bar/stirring plate system with a false floor. Thought you might consider this $70 item as true reactive temp control for anywhere you'd use the Hydor or other non-thermostat heaters...
