wow, that's rough. I've seen a few other grows (not Wurlz) where the same thing happened.
https://www.growweedeasy.com/why-did-my-autoflowering-plant-stay-so-small
Also, the foliage on the other plants in your pic aren't looking so great. Same soil mix? I've learned to not use pre-mixed soil at all except as an amendment to coco and perlite (adds the microbes and mycos to the mix).
Also, also... 1PPM water?
Can't wait to see the weigh-in. 😉
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