1300 seems a little high... might be another reason for the droop.. I had plants droop like that and perk up when watered only to droop again a short while after... turned out the soil was a bit hot... as an experiment I transplanted one of them into different soil and in a week or so, the drooping ceased. Im not undermining anyone else's advice, this is just from my limited experience... MIght want to cut back a few hundred ppm if youre feeding that amount, or just throw an extra plain water in between until you get a runoff of 600 - 800 or so gl
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All·Mix literally does it all for you – creating the optimum environment for plants to flourish throughout the year.
This heavily pre-fertilized substrate mixture emulates a rich outdoor soil with a full micro active ecosystem. It’s been designed to have enough nutrient-fuelled power to sustain lush growth for a couple of weeks, without any need to add any extra fertilizer."