Pawfly Aquarium Check Valves Plastic One Way Non-Return Check Valve for Fish Tank

Great quality check valves for a really reasonable price. Not much to these. Worked great for fixing my Keurig 2.0 K200 coffee maker which had a damaged air pump (very common problem I learned). Replaced the air pump and tested operation. Worked great but noticed water was being pushed into it, which is what caused it to fail the first time. Added one of these check valves in line and life is great now. Shame on Keurig for planned obsolescence.

They work just fine

I only had to cut the hole open on all but 1 of them. Not a super big deal it's as easy as taking them apart and popping a toothpick and then a chop stick through the little silicone pieces. Lost a star because honestly I don't feel like I should have to do this it should have been done already since that's kinda the point is for air to go through them. After that they are exactly what ordered.

Here is an honest review from a verified purchase. I have been keeping aquariums for 40 years. These are among the best valves I’ve had. They work perfectly. Any review that says otherwise was written by someone that doesn’t know what they are doing or they were using them wrong. Simply slide a paper clip or toothpick into the opening and gently open the valve before connecting. After all you want a good seal to avoid water back flow. The air has air flows beautifully. They are easy to connect using some warm water on the tubing. They have nubs to keep the hose on. These are great valves. Don’t pay attention to negative reviews.

Perfect replacement parts

Thank gosh for these! No more water going back to the air pump when power goes out. Have been using one for a long while now with no issues. Super easy to install, no extra noise, exact fit, and does what it should. I own a 75 gallon fresh water tank.

Waste of money, really bad design. They restrict the air flow greatly.

This check valve has been a solid addition to my homebrewing setup! It works exactly as intended—preventing suck-back during cold crashes and stopping CO2 blow-off from backflowing. Easy to install and gives peace of mind during fermentation. A simple but essential piece of equipment for any serious homebrewer. Highly recommend!

Got only 5 pcs

Work as expected, gotta have em in the fish room.

Good quality check valves. Only needed one but for the money got a load of spares! Functions as you would expect!

ok set a couple defective

I need this valve to use with an air pump for a plant growing in water. As the pot is not large fizzing water sprayed up over the water surface. This valve solved my problem perfectly, well aerated water but no longer any spray above. I have a 4mm tube/hose and could not push the valve in so I sanded the end and it fits. First I tried cutting the thicker bit off with a hacksaw but that was hard to do and the end was all chewed up, sandpaper is quicker and gives a neat finish !