The Fluval Pressurized 88 g CO2 Kit is the ideal CO2 supplementation system for planted aquariums 15-40 gallons in size. It will ensure that the most important nutrient is available to plants to maintain vigorous, lush and vibrant growth and condition. The kit includes: a disposable 88 gram CO2 cartridge, hosing, regulator valve with gauge for effective control of CO2 output, ceramic CO2 diffuser to efficiently dissolve the CO2 into the aquarium water, and a durable holding bracket to securely mount the CO2 cartridge to the side of the aquarium