2PK Bubbilo Water Stopper Check Valves f/ Air Tube Between Air Pump to Air Stone

Bubbilo Check Valves 2 Pack

One way check valves are used in your air tube in between the air pump and the air stone, They prevent water from siphoning to your air pump.

Therfeore check valves are the best insurance for your air pump!

How do I use the check valve?

Cut 10cm of 4mm air tube.
Connect the air tube to your air pump.
Connect the Check valve at end of the 10cm air tube. 
Connect the other side of the check valve to the rest of the air tube.
Connect your air stone to the end of the air tube.

You can add the check valve in any location on the air tube that will suit your needs.