The pump I'm using is actually what you see on top, the blue and red thing. It's called an aqualifter. It's a vacuum pump, rather than a conventional pump. Regular pumps, like maxijets etc, work too, I just had this laying around. This one is a slow pump, 3 gallons per hour, so it works well in a top off system.
I do not heat the water. It hovers at room temperature, and since I'm adding so little at a time throughout the day the tank heaters can handle it.
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