The durso stand pipe gurgle?

[big t]

With that new one it looks like water flowes over the top of the bell instead of from underneath like a stockman.

 

[lizardarm]

interesting link,
i'll have to try that one out sometime

 

[IAP Brian]

that's a cool design. It's rather like the one Lanzo at Aq. Paradise just gave me to try and improve on. If I can get it to look better, and....or... work better I'll post pics.

 

[Al G.]

I've made the HGB and it worked well. However, the one I made, I could never make a work right with the bell upside down and so I used it rightside up like a Stockman's.

I think the moveable airline is the key to the HGB and makes the overflow very silent.