If you have a power head for diffusion, you are probably in good shape. You most likely will want to turn off the co2
at night and can do that with the valve. It may be a bit tough getting the flow right every day when you turn the co2
back on, but if you are just bubbling the co2
into the power head you can count your bubbles right there.
Give it a try and see how you like it. My guess is that you will be scraping the $80.00 to buy the reg, needle valve, bubble counter, and solenoid combo on ebay soon.