nice idea. My grow area is raised up around 10” with 2 drip trays that are angled slightly down to create a catch area.
in each of the trays is a drilled hole and I just leave a 2L jug under the hole while I water and drain. Then remove when the runoff stops and put a catch tray in the same place the jug was for any further runoff drips.
you can see it in this pic.
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