JBL Proflora Co2 Taifun Inline 19/25High performance CO2 diffuser for installation within filter hose of external filter Very efficient CO2 enrichment for perfect plant growth in the aquarium thanks to its installation inside the filter return hose Cut the water return hose from the external filter, water the membrane of the diffuser, install the INLINE DIFFUSER, connect the CO2 supply hose, adjust the bubble count A bubble counter, for checking the amount of CO2 added, is integrated.