Yes I have a bubble trap.
Here's what I have currently:
Drain Tee's (my first plumbing idea was going to feed the fuge from the drain), fuge size is capped. Goes through ball valve (100% open) and then into a mesh filter sock on left of sump.
With the drain is my skimmer on stand, temp probe, ph probe, dual heaters. Under the skimmer is a new model maxijet 1200 feeding a carbon reactor which is dialed back and dumps back into this section of the sump. I figured if its under the stand it will circulate the water underneath helping prevent detrius from building up on the bottom.
Then I have an over,under,over baffle to the return. Return in the middle with mag 9.5 (bio wheel in there now to get bacteria for QT). Fuge on right fed from return pump with two balls of chaeto from diff sources (one from buddy, other from reefcleaners), 4" sand bed, and 20lbs of live rock.
I know the Tee on the drain is causing turbulence and bubbles, the mesh filter sock is doing a good job, but I don't want to keep changing them out to clean; I'd rather have this mini ecosystem filter on its own.
Skimmer has a DIY vent which did a great job at reducing microbubbles.
My advice (no matter what you do for plumbing) is run your skimmer during the cycle. You'll have lots of microbubbles as it breaks in, but better during the cycle than when you have fish.
