More Backpressure?

Can someone tell me if this makes any sense?

I have a duel overflow 125 that I'm plumbing a model 4 Proflex sump in. And the sump seems really quiet but my plumbing is loud? The sump sits all the way to the left of my stand and the long drain line is quiet but the short is pretty violent and loud. I have clear hose attaching to hard pvc to the sump and you can see lots of bubbles and turbulance in the short drain.

The short side durso comes down to the bulkhead has a 90*, 6" clear hose, 90* and into sump.

I think I might need more backpressure in the line to slow it down a little bit. What you you guys(and gals) think?

BTW I'm running a Ehiem 5000 compact at its lowest setting. 660GPH plus head loss... maybe 500 gph?

Any Ideas?

 

Well, I added some legnth to my "short" drain and "tee"d it to the other drain line. Still not any better. However the extra legnth has given me room to put a gate valve in. So Im ordering a sched 80 gate from BRS and switching one durso out for a herbie style drain... we shall see what happens !