Review on Pawfly 4 Inch Air Stone Disc Bubble Diffuser: Enhance Your Aquarium with Suction Cups! by Christine Ellis

I really wanted a disk shaped vent for my tank. This stone had many reviews and was universally popular. Perhaps, like a handful of other reviewers, I got duds. I let it soak for 24 hours and dropped it into my little 10 gallon QT using a 10 gallon Tetra Whisper pump. It only seemed to bubble up on the outside of the stone and mostly near the breastplate. I figured my pump might not be strong enough for the stone, so I went ahead and bought a 60 gallon dual outlet Tetra Whisper pump. I connected both outputs to line 1 going to the pump to make sure I don't lose pressure. And I hooked it up to this Aerostone and it just got a little bit better. I think I've fallen. Cheap $1.99 Petco mini air pump cylinders work way better than these! I would not recommend that. I'm definitely trying hard enough.