Pawfly Aquarium Check Valves, 6 Pack

Pawfly Aquarium Check Valves are small, red, one-way non-return valves sold in a 6 Pack. Each is 2.13 L x 0.553 W with 0.123 air holes and weighs about 0.1 oz, so it adds little weight to a hose. They fit standard 3/163 airline tubing. Pawfly also sells a black version in a 6 PCS pack that is a little shorter at 1.663 L x 0.53 W.

What a check valve does

When an air pump stops, water can siphon back down the airline and flood the pump. A check valve lets air flow toward the tank and blocks water flowing back. It is cheap insurance against a power outage or a pump pause while you are away.

Air only

Pawfly states these are for oxygen pumps only. They are not suitable for CO2 or other high-pressure systems, where they could crack or leak. CO2 lines need valves rated for that pressure.

Installing them

• Cut the airline outside the tank, near the pump.
• Fit the valve with its flow direction toward the tank.
• Confirm bubbles flow; if not, flip it.

Six in a pack

With six valves, you can protect every line in a multi-tank rack, keep spares, or fit one on each outlet of a dual pump like the Pawfly 50 GPH pump.

Maintenance

Clean the valves regularly. If one clogs and restricts air flow, Pawfly suggests poking it open from the inlet side with a slim stick. In saltwater, salt crystals cause most sticking, so a soak in warm fresh water helps.

Quiet running

The valves seal tightly onto the hose without air leaks and run without noise. Pair them with fresh AQUANEAT airline tubing for a clean, leak-free run.