Economically add CO2 to your entire planted aquarium with this simple Turbo CO2 Bio System! Generating CO2 by a pH buffered natural fermentation process, the Turbo CO2 Bio System can supply a tank up to 40 gallons for approximately one month. The system consists of a reaction canister that sits outside the aquarium and provides the CO2 airline tubing and a venturi power head. The power head delivers the CO2 as a fine mist into your planted aquarium system: allowing for maximum absorption. Connect to a day/night timer to prevent low pH levels during the night.