The Hydor aquarium CO2 systems are the easiest to to set up and easiest to maintain CO2 systems on the market. Everything is included in the package--even a fully pressurized CO2 cartridge.Features:A complete CO2 system for aquariums up to 79 gallonsTurbo diffuser: Increases CO2 efficiency by 40% (compared to a normal CO2 diffuser)Longlasting: Each cartridge lasts 260 days at 4 bubbles a minute.Simple and safe: Autoregulating pressure reducer with precision valveMaximum efficiency: Results visible in 2 weeksPerfect control: Special glass bubble counter for perfect visibility, regulation and controlSuper-safe disposable charge