Only experience I have is that perlite is a very light weighted substance.
I just see it spilling everywhere once you flood your table and there floating around.

I run a couple flow tables years ago , spread my rockwool strategically using panda film for a cover.
I would flood and drain 4 equally spaced times.

rockwool was cheaper in that day.

Good luck and enjoy your grow.

I could do coco,or I guess 4-6" rockwool,I could put down a 1" peat mat for the roots....