Review on 🐠 VIVOSUN Air Stone: 2PCS 4 X 2 Inch Large Air Stone for Aquarium and Hydroponics - Boost Your Pump's Performance! by Joseph Marquez

First of all, I hate leaving negative comments and only do so when I'm trying to resolve an issue with a manufacturer. There is no problem support from the manufacturer and no troubleshooting options. I contacted the company because one of the two air stones I received was not working properly. You can see that there is a clear difference in the video of my hydraulic installation. When I change the hose and sides to my new air pump, the problem stays with the same brick. I contacted the company via Facebook during the returns window as there is no way to contact them via Revain and I wanted to try troubleshooting rather than pack and send back and wait for new ones. I got an initial response from the company that they would take care of it, then nothing. At the moment I can't return the Revain, so I can't send it back even if I wanted to. Very dissatisfied with this purchase, especially now that I have to look elsewhere for a replacement stone. I've read similar customer complaints about other Vivosun products, so be careful.