The problem with having your controller control everything

[whatcaneyedo]

I'm comfortable with my controller handling all of the conveniences. ATO, lights on and off, cooling fan, C02 solenoid or dosing pumps etc. But if possible I like the idea of having at least one circulation pump or powerhead plugged directly into the wall. That way if the controller goes down I don't lose critical flow. Without flow, oxygen can quickly deplete causing the inhabitants to suffocate. I feel confident that my tank will be fine without its ATO, lights, supplements etc for a day or two while I convert everything back to hardware store timers and top off the evaporation myself. But I don't think it could last for more than a few hours without flow.