You mean I don't know how to tell a dark green leaf because I look at it under blurple light?
My stance after two grows, and accounting for my OK growing skillz is this...I gotta get me better lighting to get more THC content than my present $99 BestVA 1000w LED.
Dark green: it seems like the "blurple" spectrum is pretty good at turning out really healthy dark green looking plants that actually dont preform that well. Maybe something in the spectrum hitting reds and blues which are the absolute basic for plant survival making the plant look better than it really is. Im not sure about this effect but ive seen and people have commented on it repeatedly.
Changing lights is not going to hurt your grow can only really improve it. White light leds with high efficacy is the way to go.
On potency:
Lights: most people seem to get decent quality under blurples, just that the yield isnt there. You saying no potency, and by the looks you got very nice yields. So maybe not only a light problem? I think going from 20-4 vegg to 12-12 might be the a problem: the plant reacts to how much light it gets daily and you had to cut it by 40% to get your plant into flower. Tricomes are generally thought of as a kinda of defense mechanism and you wanna take Daily Light Intake DLI up rather than down in flower. Again, not sure, but this is a thought
Strain: auto ultimate: first there seems to be a consensus that most auto strains, even if your turned out to be photo, are weak tea. Also, if you got this directly from dutch passion (its an authentic seed?) Well if it turned out to be photo god knows what happened and probably bad potency. Another issue: heard some people where disappointed of auto ultimate first impression but better with a long slow cure.
Nutes: it worries me a bit that youve not even touched on the nute recommendations and questions above. You seem to have an attitude of "please confirm what i think is wrong, which btw is not my fault" and not touch any questioning on your nute regime which pretty clearly has given you some burnt leaf tips. You never mention EC in this grow, or if youre using RO water or tap water, and what is the EC/ppm of your tap water. Im not knowledged enough to say your nute regime is guaranteed too much, but youre searching acknowledgement that its not the nutes: anyone who knows their shit knows that youre regime is impossible to evaluate with out this basic info and it being missing makes me suspect that this is simply something that youre not checking for. Would also be good to know how you ph, after the nutes right? But how much time and mixing happens before you ph?
Maybe this is anplace to start, to give your basic procedure for mixing feed? What order, how do you know if you use too much or too little of each? Are you sure your not just reading on the back of the bottles because thats just recommendations and usually a little bit high. You need to read your plant if you want to be sure.
Also an idea: you mentioned Megacrop nutrients i think. Suppose to be a complete nute, no need for anything else, it contains everything that my mates pro-grow does (he adds everything separately). Maybe ditch the dozen bottles and keep it simple? But in that case try it on a photoperiod; autos on complete formulas jumps almost straight in to flower, no vegg and shit yield.
Peace out
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