PRO-SE Series - Aquarium CO2 Dual Stage Regulator with Integrated SolenoidCO2 systems for planted aquarium tanks by Co2Art. Turn your aquarium into a natural beautiful piece of art! Affordable professional grade regulator perfect for the beginner just starting out with CO2. One manifold output for one aquarium. CO2 is arguably the most important element in the planted aquarium. It is required for respiration and growth by all aquatic plants, used in a process called photosynthesis. Plants require a constant supply of CO2