Very nice Dufflight ! ....Thanks for sharing the pictures.

I'm working on building a swirl filter for my system. (not using rocks/hydroton in my GB's)
I noticed in your picture, of the outside of your larger swirl filter.... you have two (2 inch/50mm) pvc lines ... inlet and outlet perhaps ? Plus, there is a smaller tube, also going into the tank...?....is that an airline ?
I wouldn't think it would be....as that would stir up the water, when your trying to control the flow so the solids collect in the bottom center.

I just looked at the picture again and noticed that one of the larger pvc lines is not hooked to any thing. Is that water flowing out of it ? So perhaps, the smaller line is your water 'in'...? The 2 larger lines are both outlets...?
I've lost one of my primary colors in my monitor...makes it tuff to see well. Spending my $ on aquaponics instead of a new monitor