Yeah i've heard of a lot of people getting aggravated with the stuff, its weight, precleans/soaks, cost.
Your PH and EC probably jumped around like crazy too, no? Good to know you were successful with your 20gal, feel a bit better about using the 40.
This is the traytop I made, going to cover that grey tarp with white poly and covering the pots with some hydrofarm pot covers. The pots fit perfectly in the holes and underneath supporting it all is 3/4" pvc pipe I cut in half the long way and used each half for a channel to rest the rim of the pot on. Then took 3/4" tees and cut those in half also to keep them even with the channels and made columns in the middle to support the weight. After all this I still like your pot setup better, so much simpler.
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