I did a durso as well, very quiet. Just have to find a non threaded cap. But that's panning out to be a wild goose chase.

the only downside tome using abs pipe is that i have to sylicone the pipeto the glass which willmake it vry difficult for testing purposes.. maybe i shoudl just use 1"1\2 ...dang it i think i need to drink on it maybe lol

I had a duroso and ended up changing to herbie. If you are going to be pushing 1800gph through your sump you will need a very good bubble trap to catch the micro bubbles from a duroso. With water moving through your sump that fast you'll end up seeing a lot back in the DT. I would suggest going herbie if you can with 2x1.5" returns. It's always easy to decrease the drain size with an adapter, but once your tanks running you can't really increase it.

I would also suggest going flexible hose for your return, saves on plumbing parts in the end, cuts noise down greatly, and also increases flow by a lot without having 90's in there.

you make a good point on sump flow ive been concentrating on flow within the tank and forgetting the sump and skimmer capabilities. i have to re think this again and maybe approach this another way. :frusty:

as far as flex tubing i cannot use this tank side but will have a chunk sump side to reduce vibration. the sump itself will be sitting on a foam pad to also reduce vibration