You should try to use about 3 or 4 of the 4" stones. The more the better check the lines one at a time you could have a clog or a bad stone.
Zandor Reviewed by Zandor on . Crappy Bubbles... Hello, I started today to experiment with a bubbler setup inside a 6" pot. Here's what I've got: - 6" pot - 4" air stone - air pump with dual outlets. Now, I plumbed both air outlets with a "T", so now I've got one outlet... When I drop the airstone into the pot, it does make bubbles, but kind of shitty. Rating: 5