One-Way Check Valve — 2 Pack

The cheapest insurance in the hobby. A check valve in the airline stops water siphoning back into your air pump during a power cut — the classic way pumps die and floors get wet.

• One-way flow. Air travels to the tank; water can't travel back down the line.
• Fits standard airline. Push-fit on 3-5 mm tubing — trim the tube end square for a tight seal.
• Fit it low. Place the valve below the tank waterline, between pump and tank.
• Two per pack. One in use, one spare — or one per line on a dual pump.