A few weeks ago my regulator went down. I picked up another regulator (thanks Dudley) as a quick fix. I then remembered that the people on the planted tank forums were always talking about DSRs (dual stage regulator). After asking some questions to the local expert on the subject (Matt on SFBAAPS) I decided on getting a Matheson 3810 regulator off ebay. The Matheson I picked up on ebay has a full stainless steel body and was brand new. I got a steal of a deal on the regulator at 115 shipped. Retail price on one of these is ~1000 dollars. From what I've gathered the big difference between a dual stage regulator and a single stage regulator (what all typical aquarium regulators are) is that the dual stage will keep the working pressure constant no matter what the tank pressure is. A constant working pressure will give you a rock solid bubble count through the life of a co2 tank. No more fiddling with your needle valve to get the right bubble count. This regulator was made for a different type of gas, so I ordered some stainless steel cga320 fittings off the internet. I also purchased a stainless steel check valve swagelok/nupro 1/3 psi 1/8" FNPT. I also went with an all stainless steel post body kit from someone local. Kit included 1/4" to 1/8" npt reducer 1/8" npt nipple 1/8" female npt elbow manifold for block solenoid numatics stainless steel block solenoid Swagelock 22 series metering valve with adapters First I removed the working pressure dial Next I removed the 1/4" valve from the output. The reducer went in Then the elbow and nipple Manifold went on the elbow Metering valve then got added Added the check valve and the JBJ bubble counter to the elbow after the metering valve And attached everything together Finally the solenoid was added to the block manifold I have yet to add the stainless cga 320 fittings, as I am waiting for them in the mail. I will update when I add them.