Euroreef Sponge Bubble Difuser - Don't use as Prescribed

[kwirky]

actually I did some research, and I got the gatevalve mod mixed up with the recirculation mod.
looks pretty simple. you find a gate valve the same size as the riser tubing (or close), and attach it where the riser tube would have gone. then attach a T, then feed the output back into the sump for a quiet output. Looks WAY easier to dial in than raising and lowering that riser tube.

i found an image of it on thereeftank.com


I think this is a recirculating model, too