Co2 production and supply are carried out fully automatically and in the right quantities nothing needs to be set or measured the ultimate in simplicity and convenience this makes dennerle bio co2 ideal for all those who are new to co2 fertilization and for those who want to try the method out youll see results after only a few weeks of co2 fertilization plant growth improves substantially the plants are greener stronger and display greater vitality your whole aquarium will be brought