Hydor’s CO2 GREEN NRG Exclusive solves the problem of low carbon dioxide in fresh water aquariums: easy-tech system with CO2 cartridge, easy to use, with unique diffuser technology which guarantees maximum efficiency for visible results in only 2 weeks. Turbo Diffuser increases CO2 efficiency by 40% (compared to a normal CO2 diffuser). Long-lasting: 260 days at 4 bubbles a minute or aproxamately 3 months on a typical 30 gallon aquarium. Simple and safe: Auto-regulating pressure reducer with precision valve. Maximum efficiency: results visible in 2 weeks Perfect control: special glass bubble counter for perfect visibility, regulation and control. Disposable, inexpensive CO2 charge super-safe disposable charge: over 1,5 million bubbles guaranteed.