Ok, a legend/key for the sketches above...
- Display drains are 1.5" PVC w. flex where entering stand
- Refugium drains are 0.75" PVC via mini-Beananimal
- All 3 return pumps are via 0.75" PVC (or Eheim flex)
- Heater is red
- Water lines are noted in black
- Drip tray area has two sections, same media - one is 'dry' the other 'wet'
The water level in the middle area of the tank dictates how much of the pot scrubbie media is kept aerated. That middle box area housing the scrubbies will essentially be packed full, so no flotation issues.
For the refugium, I wasn't sure what my options were...aside from taking the XP1's top and creating a weird little section in the sump for it...so instead I got creative! Or overcomplicated...
Refugium plumbing design
As mentioned, this will be essentially identical to the display overflow/drain setup, except I'll drill holes in that side of the sump to pass through the 0.75" PVC. The refugium itself will have 0.75" bulkheads...but didn't see a need for them on the sump side. If the water ever gets that high, I have way more serious issues to deal with. (I don't even think it's physically possible due to the overflow designs...even if the returns go into full siphon)
I'll then have another small return pump go over into a spraybar or just an elbow, not sure yet. I might even just use the spare 3/4" tubing instead of hard line. The nice part about this is I continue the theme of designing flooding out of the setup. If the power goes out, overflow finishes emptying, done.
If anyone can point out issues with this or have better ideas how to plumb the overflow back into the sump, please chime in! The only 'issue' I can see being raised is more complexity equating to more work to implement...but not more complexity = more points of failure, as the overflow/drain design I'm confident in.