ThanksThis is the valve I picked up. The pH controller has a 120v output (kinda). So, with that valve I just connected the wires up to a 12v transformer I had laying around from who knows what (an old router or something probably). The nice thing about these valves is that they draw almost no power when holding open, so just about any 9-24v transformer you have will work just fine. The only thing you'll need is a adapter to go from the valve to the tube. In my case, it was a Male 1/2"NPT to male 3/8" barb.
I have a similar valve (but 120v) for my RO system. I plugged it into a timer. Any time I need RO water I just set the timer for how long I want water to run for and I can walk away without worrying about it overflowing.