I've been using these for a couple months now and have had no issues.
I haven’t tried these out yet but I’m still building other parts of my fish room. Need to watch Cory’s videos on modifying sponge filters with these air stones.
After watching several videos about these I decided to give them a try and boy do they work. Bubbles are big and allowing my bottom dwellers plenty of air :)
Great item and as always Cory's product reviews are truthful and unbiased
Extremely fast, effecient service. Cory and his crew really are top notch in the fish community!!