[untamed]

I can't believe that it took me 3 years to figure this out.... doh!

2 years ago, before we air conditioned the house, the tank was getting too hot. So...I naturally installed central air conditioning to the entire house.

That prevented the tank from getting too hot, but there was still a significant high/low day/night swing in the temperature. For some dumb reason, I figured that by keeping the tank warmer at night, it would minimize the daily swing. Stability is better than instability, right? I adjusted my heaters to keep the tank at 79 overnight.

It only just became clear to me that this didn't really work at all. Each day, the lights added a certain amount of heat energy to the tank, while the air conditioning was able to remove a certain amount of heat energy. That all happens mostly independently of the temperature that the tank happens to be every morning when the lights start up.

In other words...the tank goes up about 3-4 degrees every daylight cycle, and it is going to do that regardless of how cool I allow the tank to get at night.

So...I've decided that a range of 78-82 is probably much better than 79-83. In fact, I'll probably end up dropping it right down to 77-81 or even 76-80.