I took a pallet that was 120cm * 80cm and cut a third off the pallet to make it 120cm*60cm. Then I screwed 2 pieces of 2*2 50cm long underneath the pallet to raise the top of the pallet 20cm (8"). This probably explains it better. The pallet is the width of the tent so you need to set the 2*2 an inch from the edge of the pallet so it doesn't sit on the tent poles.



I hand water daily and collect run off, I grow in compost with organic feed otherwise I would have raised it higher and put a reservoir their to recirculate.

I suspect someone else could adapt something like this to sort out there grow spaces.

If i wanted to make the whole tent run off though I would use a 1.2*1m pallet raise it to 30cm then screw 4*4 of ply to it, turn the tent upside down and then use a 1.2m tray and put a hole so the tray drains through the upside down tent vent hole and into a tray that you and pull out to drain.

15l's should be 3-4 days run off for me but I will empty daily I wanted a comfort zone as I might have to go away for a few days in which case I will dripper them with plain water if I have to go away not ideal but should only be once. I'm looking for a bigger tray I should be able to fit a 40l tray there which would give me over a week in an emergency.