So here's my question, we can all agree that setting up an ATO for an aquarium is pretty easy and straightforward. However here is my situation.
Inside building 1 I have 1 75 gallon and 1 100 gallon (both tanks include sump water volume).
Inside building 2 I have 1 65 gallon, 1 75 gallon...
I have a larger container for my water, pump and tubing. Looking for controller and sensors. Or a cheap way to do DIY it.
Cheapest I found online was:
Aquarium Maintenance & Plumbing: Auto Top Off Controller
Can't afford to spend that much. Any ideas or sales?