Your growing technique is close to perfect but the lack of wattage is costing you soo much in quality and quantity, after seeing the whole diary, the way in which you mainline and the general health of the plants is impeccable but please put in at least 2 more of the greenception 4 cob's, don't fall for the lies told by these led companies, yes they are 30-50% more efficient than a original hps however at a true wattage of 128w each that is only comparable to 200w of hps each, which is perfect per plant but no way near enough umol for 4 plants thie size of which you are growing, I can ensure you that if you had one 4 Cob per plant you would be getti g around 6-9 oz per plant.
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