Fluval co2 cartridge for the pressurised co2 kit 88g this is a disposable cannister to replace used cannisters on your fluval co2 kitr this cannister may also be suitable for use with other co2 kits such as the aquagro hobby and expert kitsr aquatic plants require co2 to grow and remain in optimal condition the fluval co2 range ensures that optimal levels of co2 are avalible in the aquarium to maintain vigorous lush and vibrant aquarium plants