After hunting around for egg crate grill :angry:
I found a company that deals in air con supplies
Had a chat to the guy there and bugger me he has an "O"
next you know free egg crate grille

and filter material "As much as I want for free

they use it as packing then toss it
I bought the noodles lol
Rough idea of measurements I wanted I set about it
The red strips support the trickle tray above the bio balls
a view towards the feed end
Drying as I'm writing this
Plumbing is all ready to set up when the sump is in place
Cheers Gaz