Why you want to do it? The degassing very first chamber is really making everything dead silent. I mean if you want to remove it and plumb directly to roller mat?
If I to do it I would add glass cage around overflow from the pipes chamber (currently its wierd shape opening) with silicone and bulkhead at the bottom and hard pvc plumbing, but not sure why I need this?
The 3D printed adapter is far too loud even with adding filter pad to try and silence it. I’ve seen a number of others that removed the glass in the first chamber and plumbed it directly to the reef mat.
I’m using Reef Factory mat and it has a marking of water level on a side, showing where your sump water should be. If my water level in sump is at this marking, I have zero noise.
Just my 2cents to check before going on ripping glass…