So the tank is running. It is cycled and has a few fish. Time for the ATO.
I did not want to put a reservoir under the tank. So I left 7 inches between the wall and the tank to tuck the reservoir back there. The tank has to be about 4” off the wall anyways, and being the 7” off doesn’t look bad, and allows some access back there to get to exterior overflow box, ball valve for UV etc.
I had a custom reservoir made by Tenecor. It is 24” long, 20” high, and 6” wide. 12 gallons total but will end up being a little less. I wanted to employ a system using a solenoid valve and float switches to fill the reservoir automatically. I looked online and found the proper relay, and floats. However after talking to the guys at Auto Top off.com they told me they could provide everything I was looking for. The whole set up from them was $75. It has a high float switch, a low float switch, a 12v normally closed solenoid valve, and a power supply. Obviously I had to purchase the reservoir, and whatever method I wanted to use to fill the sump. I went with an Avast Marine pressure switch.