Our Premium Dici CO2 Regulator with Integrated Solenoid is perfect for many CO2 injection applications to aquariums. It has been shown that CO2 enrichment at two, three, or four times the natural concentration will promote plant growth.  The Dici Premium CO2 regulator includes dual gauges (in both psi & kg/cm) complete with buble counter that has non-return function and a needle valve for fine tuning the amount of CO2 injection to maintain the desired level of CO2 concentrations to achieve optimal plant growth