Shower Cap is instrumental in the condensation and drip drip drip back into the top dressings as well as to help combat bugs - that’s a free insurance policy, thank you ....
I have seen a few trial grows, one by BuildaSoil - EarthBox with cap verses EarthBox without cap but that one had a cover crop ..... cap was way to go .... another trial Grow was a guy named Pedro - you can check him out on Instagram - Pedro went from pots to LOS Big Box Beds with cover crops to an EarthBox, then four boxes verses LOS Bed then tried cover crop and eventually ended up with the cap, right back where manufacture directions said, but myself all that happened before I grew my first EarthBox but like Pedro I tried pots at same time and even the same soil and the EarthBox out grew all my pots combined - but then the strain could of been big factor ....
Lot of ISIP containers, even the five gallon homemade will have a cover cap - not all but most as rain water falling in would add to the wicking water and overwater for sure with Good rain but indoors no worries there .....
Mulch will have similar effect, it’s usually damp under the mulch but why not mulch and a cap
@Organic Sinse or would that create issue when top watering or do you top water?