I am trying to complete this scenario
"....They have PH testers that when hooked up to a H20 Pump will turn the pump on when the PH moves out of the desired range. You use them by hooking them up to a small tote filled with water PH'd very low. When the PH rises the tester will kick the pump on, the pump should be set up to pump from the small tote into your 5 gallon reservoir. This will pump enough low PH water into your reservoir to stabilize PH automatically while you are gone. This will also help to keep your res topped off."
When he says H20 pump, what kind? This person ia doing the same thing I want to do.