I was unable to find a small enough wooden airstone to fit, so I improvised. I took one of the small green airstones (cheap!) and fed it with airline tubing down the outflow channel.
... If I remember correctly, I was able to get the top black ring and the clear tube/sleeve that goes between the inside short tube, and the outer wall off the unit. So I took that sleeve out, and cut a notch in the bottom of it. I put the airstone in through the outflow area and ran it to the bottom an close to the inner short tube. the I replaced the "sleeve" making sure the notch I cut went over the airline tubing, to hold it at the bottom of the unit. I replaced the top black ring and put the seaclone back on the back of the tank. (Put an inline watercheck valve in to prevent a backflow of water)
The only other thing I did was to get rid of the little black airflow valve they provide and got a little plastic valve from the LFS. That makes it easier to dial the flow properly.
I wanted to cut down the center tube a couple inches, but I don't have a dremel tool, and my hands are too fat. So I didn't. Turns out I didn't need to. It's working well since the mod. It took about 1-1/2 weeks for it to "break in", and now I get at least 1-1/2 inches of nasty green/brown skimmate weekly (it's only a 29 gal tank).
That what I've done and it made my seaclone a perfectly functional unit (so far), but I'll not buy another one. I'll get something better.
Later,
Brian