Hi, UK based here. I'm looking at setting up my first grow. Thinking of running hydro RDWC system, not sure how many pots yet? Good rule of thumb is 1 plant per Sq foot is this correct? Ideally i would like to run a closed loop system but these can cost quite a bit of money to set up. Will be using 600w hps lights. Could anyone give me any tips on running a system like this please?