Grid for Flood Table

I saw somebody using a grid on the top of their flood table for better drainage. I recently switched to GEOPOTS and the water doesn't drain as well my pots do. Does anybody use or know of something like this? Tried the search but had no luck. Thanks!

I used the layin plastic grills for ceiling tiles, they come in 2x4' and i think 2x2'. They are easy to cut to size and are about an 1/2" thick with a 1/2" grid. My trays r not perfecly flat so the water moved freely under them. I believe there are also matts that r available for drainage, but i also couldnt find anything either.

What waterdawg said. They are light diffuser's found in the light section of big hardware stores.

http://www.homedepot.com/p/Plaskolite-4-ft-x-2-ft-Suspended-Light-Ceiling-Panel-1199233A/202025149?N=1z118j1#.Ujtp9H_k2Ng

Gonna roll with this, pretty sure it's what i saw somewhere here or on the net. Thanks guys

Yup thats it. Good luck!