The Dennerle CO2 Special Check Valve reliably protects CO2 appliances from water intake. Why does water flow back into CO2 hoses at all ? Putting it figuratively, CO2 has a rather strong urge to dissolve in water. If the CO2 supply in your aquarium is interrupted (because the CO2 cylinder is empty, the cylinder valve is closed, the CO2 nicht cut-off is activated, etc.), the residual CO2 left in the hose will also dissolve in the aquarium water. This gives rise to a vacuum in the CO2 hose, which literally causes water to be sucked into the hose. The result: connected CO2 appliances may become irreparably damaged by corrosion.
CO2 is a very special gas and has a very difficult physical characteristics than air, for example. This is why Dennerle has developed the CO2 Special Check Valve for use with CO2. The heart of its is a permanently elastic CO2-proof special membrane. It fits tightly-stretched onto sealing rims. Two threaded hose couplings ensure a CO2-proof connection. Attention: Do not use normal air check valves, as these may become brittle through contact with CO2 within just a short space of time, making them leakly. This often occurs unnoticed.Do you have questions about this article ?