Although The Grizz may be able to help you quiet down your Durso, I hate to say I mentioned awhile back in your build that Herbies are notoriously easier to deal with
I'm not by any means saying I told you so
but it's something you should consider before you get too far along with your build
If you recall, I
rebuilt my sump 3 times before I was happy with the noise and flow
It wouldn't hurt much right now to try some other plumbing, right ???
Herbies don't require downturned pipes or air inlets. Just a submersed main drain. Once the air is flushed, away they go with their full flow
I installed a gate valve on my main drain ( thought I would need it ) and I keep it wide open , with the pump bypassing in the sump as the pump is more than my overflow can handle ( my situation doesn't count here - my sump is only a few inches below my tank so there's not enough pressure to flush the drain )
I keep my main high enough that the box doesn't drain much when shut down and the emerg is close to over-full with a float valve above that to shut off the pump, just in case
Very simple
I haven't had to adjust it once since I started it last month and it doesn't go up and down more than a 1/4" in the overflow box
I wish I could say the same for the level problems I have with the other pump in my sump with the chaeto tank, uv, chiller, skimmer and reactors
