hey Ayeydized
how tall is that tub ? , i ask because water will generally only wick up around 30cm in soil
not sure about coco but i suspect it'd be the same
how do you plan on filling the reservoir ? , watering through the top of the soil is not the best of choices imo
i've used eathboxes a bit & what i've seen is , when soil wicks from the bottom it can stay quite wet , by watering
from the top as well you'll run the risk of over watering easily , if you can put in a fill tube in the corner like an eathbox
& only water via the reservoir you'd have less chance of over watering i reckon
& if your plan is to let it dry right out before watering again through the top , that's not great for your soil biology / worms / composters
plus it'll flush allot of the nutrients out into the reservoir , might be ok in coco i guess but any plant outdoors will attract organisms to it's root zone
the eathbox uses a plastic cover or shower cap as some like to call it , just like your plastic lid cutting idea , neither will stop bugs getting in
on an earthbox it's used to conserve water , it will block evaporation , condensation will biuld up on the underside of the cover & drip back down
to the soil surface , outdoors the cover will help block rain from watering through the top & causing the plant to become over watered
my first run with earthboxes the media was 66% peat moss 33% perlite vermiculite mix , the res was filled with water & EM-1 & i used a bokashi
fertilizer ( which is also made with EM-1 ) & worm castings , like this
when you used the cover the top soil stays moist & roots will utilize all the soil available top to bottom
here's a couple of eathbox pic's i still have on my phone & another pic which is the oz version of an earthbox called Greensmart pots , the mycelium you see came mostly from the bokashi fertilizer i used
& the consistent moisture under the plastic cover
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