anyone ever seen this problem?

plants are 72 days in flower
finishing soon i hope
i've been giving some pk13/14 lately along with the 8-6-10 coco fertilizer. I was giving 1.5 EC, now I give 0.7 (also give some molasses)

so yeah they grow in coco
these are hindu kush

would love to hear what you think about these yellow blotches in the center of the pic. also seeing rust spots on the now. These are upper fan leaves of the buds, also seeing some of it on the small bud leaves.

i thought it was light/heat, but i'm pretty sure it's not


How long has this problem been going on? 10-14 days
Are you growing in a PVC grow tent? (example: Hydrohut or any other non brand tents) no
What system are you running? (DWC? Ebb flow? Aero? Water Farm? Flood Tables? and so on...) coco pots, drain to waste
What STRAIN are you growing? hindu kush
What was the establishing technique? (Were the seed or clone?) seed
What is the age of your plants? total 4 months now
How long have they been in there mixture they are in now?(coco,soiless etc..) always
How tall are the plants? about 3' i'd say. they are scrogged.
What PHASE are the plants in? (seedling, vegetative or flower) are the plants in? end of flower
What Technique are you using? sorry?
What substrate/medium are you using?(Hydroton, RockWool etc.) coco-perlite 50/50
What is the Water temperature? N/A
What color are your roots? White? Brown? Are your roots slimy? Don't know. Possible that they are somewhat brown and weak.
What Nutrient's are you using?(If growing soiless) HESI coco, pk13/14, supervit, powerzyme, molasses and sometimes magnesium sulfate
How much of each nutrient are you using with how much water? usually 1.5EC (750ppm), now 0.7 (350 ppm)
How often are you feeding? (If using soiless) before, every 6-7 days. now, every 3-4 days.
How often are you giving nutrients? (If using soiless) before, every 6-7 days. now, every 3-4 days.
If flowering, when did you switch over to using Bloom nutrients? I actually been using the coco (8-6-10) the whole time. It's mostly a bloom fert but my veg was excellent, actually.
What order are you mixing your nutrients? (example: veg nutes 1st, bloom 2nd ect) first coco, then p/k, then molasses/epsom etc.
What is the TDS/EC/PPM you are using currently 0.7 EC
What is the pH of the "Tank"? 5.8
How often are you testing your pH/PPM/EC/TDS? every feeding
Are you sure your calibration is correct on your equipment? yep
When was your last watering? today
What is your water temps? 71
When was your last feeding change? (ie. grow-bloom-micro-additional) I'm not really consistent, I change a lot.
How often do you clean your system: example: Flush out water replace with clean water and nutrients? I flush them constantly, today I flushed too.
What size bulb are you using? 400w HPS
How old is the bulbs you are using? not sure
What is the distance to the canopy? pretty tight. about 8-10".
What is your RH Factor(Relative Humidity)? 45-70.
What is the canopy temperature? 84-86. at day
What is the Day/Night Temp? (Include flucutaion range) 10 degrees difference I think
What is the current Air Flow? (cfm etc.) not sure
Tell us about your ventilation, intake exhaust and when its running and not running ? vent out take with a 160 cfm centrifugal running from the cooltube, and another 240cfm just moving air out of the closet. I have the close the room completely during lights out which spikes RH.
Is the fan blowing directly at plants? yes on the canopy two fans.
Is your water HARD or SOFT? RO water

If using RO,Distilled,mineral water, what is the ppm/EC/TDS without any additives? about 0.08 EC

Has plant been recently pruned, cloned off of or pinched no

Are plant's infected with pest's Not really. Maybe some thrips I dunno but it's under control. I use neem.