Built a new wet/dry for my rays. Need some input.

[jeffers]

looks great thanks for sharing.

 

[MeAko]

a tray that is 3" deep.

I would try to squeeze in as much mech filtration into that 3" tray as possible, maybe multiple layers of different kinds, start with coarse on top and then fine at the bottom. If possible maybe you can add some more layers of mech filtration below the tray as well, just to try to keep the scrubbies and bio balls free-er of dirt.