Anyone have a guess to whats happening to the leav...

This was undeniably from heat stress! There may have been other problems making it worse, but overall try training the plant down with a method called Low stress training (LST) or topping to create multiple apically dominant stems for a wider canopy. Looks like the final results were pretty good however congratulation 😎

Hi @Grow413! Yes the discoloration is a normal thing, the process of senescence is responsible for this. Now, your curling-upward leaves are not a normal thing, they are a sign of heat-stress, your apical summits were probably too close to the light, and/or your airflow was not good enough to protect those colas from heat. Congrats on your harvest 👊

Hello @Grow413 ! That's a humidity stress not because the value of RH that you have is wrong (especially for the flowering stage ) but because the 40% RH in combination with heat gives a slight high VPD. So it's a heat problem that is expressed through humidity stress symptoms. Tow options you have. First option is to raise the humidity at around 50% and the second option ( and best to do ) is to lower the temperatures at around 22-24 °C. If the lamp is the reason for the extra heat that you have ( 25 cm is very close to the plants ) then raise it. Happy growing ! 👊

I would raise the light 4 inches and switch to a 10-14 light schedule it wont be long before they start fox tailing the more fox tail your thc starts dropping u will lose taste and smell think of it as you going get a bad ass sunburn i would reduce the light raise it and just soon cut off those leaves at this stage it really doesn't matter 👍👍👍They taking more energy from the plant 👍👍👍

Heat and light too close.

I would say you need to move your lamp away from your plant here , the one plant is fine because it is further away but the one plant shows 100% signs of heat stress .The leaves making a sorta taco shape and folding upward like that is a classic sign , and at this point I would say it wont be long before you start light burning the leaves on that plant . In the 6th picture I can see begginig signs of nutrient burn but i also see that leaf is curled up so it could very well already be light burn affecting the plant . There's a few things that lead me to belive its light burn and not nutrient burn . Looking over your diary I can see in your stats that your nutrient solution isnt too strong so there should be no reason for burn to be happening . What I see how ever is that it is geared to veg and not flower . I would suggest to correct your solution to a more bloom oriented one . All in all looks like your in good shape ! I would just move the light further away from the plant and fix your nutrient solution to be more bloom oriented and you will be rocking and rolling in no time ! I hope this information serve you well on your journey ! - Happy Growing!

Under HPS light it's imposible to see real colors, you need to give us pictures under white light. What can be seen is leaves folding up, in a canoeing shape, usually due heat stress, when the light is too close; and at 10 inches from HPS the taller plant is suffering, put more distance to the bulb. Also there's signs of overfeeding, dark green leaves and burnt tips.