Sump refugium question/dilemma

[prime8reef]

I'm building a custom sump with refugium. Question:Is there a simple design to create a 'blow by' around the refugium to decrease flow in the refugium without losing flow through the sump from overflow to return chambers?
Or a slide gate to reduce flow in just the refugium?
I want to keep a good population of pods in the fuge but don't want to lose the 30x turnover rate I'm planning for the tank to sump ratio. Also don't want the massive flow to blow the pods out of the refugium when it's seeded.
Anybody ever do this?

 

[heathd.hd]

Here's my design on my diy build works great for me. Drawing was preliminary and the picture was close to done. This is 2 pieces. But you get the idea. Duel intake with a valve on the refugium side to limit flow.

 

[heathd.hd]

A different one I built. This was 3 pieces. For a single door 3 foot stand.