I have a Gen-X CO2 regulator by pacific coast imports. It has a solenoid and a needle from MRC http://www.myreefcreations.com/caaccessories.htm at the bottom of the page. Currently the regulator is putting out an output pressure of 25. That is just a touch higher than I want. There isn't any big knobs for the output pressure. On The bottom of the setup there is a round spot with a slot in it for a screw driver. I think that is the output pressure controller. I turned it about a 1/4" of an inch both ways and nothing really changed. I didn't want to turn it too far if that wasn't what I thought it was. Anyone one how to change the output pressure?