This product has forever changed the introduction of CO2 into an aquarium.Used for CO2 injection for a freshwater planted aquarium, or a Calcium reactor in a saltwater application. We guarantee that nowhere on this planet can you find a BETTER or MORE PRECISE regulator! This is OUR baby, we built it, tested it, and patent it. The problem of "dumping" is completely eliminated with this regulator. Dumping is always a problem with ALL OTHER regulators which utilize a needle valve. Simply because, a needle valve relies on the pressure on both sides of it for it's accuracy. So, even though you have it set at a certain "bubble rate", once the pressure in the cylinder (or the outside atmospheric pressure) changes, so will the amount of CO2 that passes through the needle valve. This is why it is physically impossible for any and ALL other regulators that rely on a needle valve to ever be consistent. Our regulator does not have a needle valve, but instead, it has an electronic valve that opens and closes in a fraction of a second, (each "opening and closing" equates to a bubble) and, due to the fact that it is "electronic" the "bubble rate" can NEVER change. Once it is set, it can never vary more than +/- 1/1,000=of a second. The low pressure gauge goes up to 30 lbs.