Passive irrigation brain buster question

Hi all,
I'm setting up a small scale grow. Sog style with plants tight together. I'd like to use passive irrigation to water my plants. I know I stand the chance of drowning roots this way. I know the right growing medium is the key. So my question is. What is the best medium to use in a passive irrigation system?

To be absolutely clear, I plan to put potted plants in large tray with 4 in walls and fill with water nute mix and leave until it's all soaked up by pants

I'm new to this but at a gess.

Perlite 70%
Vermiculight 30%
and maybe an inch of Grow rocks on top to stop Algue growing.

I heard pure rich potting soil was good, but for such a system i heard vermiculite or peat moss.