JBL ProFlora CO2 Set Professional are professional CO2 systems with control computer for automatic CO2/pH control in all freshwater aquariums from 40 to 600 l capacity.There are three models to choose from, which are identically equipped except of the CO2 compressed gas cylinder. This CO2 system leaves nothing to be desired. The control computer with graphic display and intuitive touch operation permanently measures the pH value (CO2-dependent) and regulates the CO2 supply based on the set values. A pH electrode is required for operation, which is not included in the scope of delivery.Why a CO2 system is necessary in the aquarium:: Plants provide the aquarium with vital oxygen for your aquarium inhabitants, prevent algae growth, remove pollutants, provide hiding places and reduce pathogens. Plant fertiliser systems with CO2 cylinders supply the plants with the main nutrient CO2 through the water. The plants absorb this and convert it into sugar and oxygen in photosynthesis with the hel