Dont have that much experience but it looks like you could have powdery mildew on your leaves. Open to being corrected on that though...
This white spots are caused by humidifer, its on almost 24hours a day. I've got 2 dutch passion euforia plants in the same tent, and they're looking great. I only have problems with cheese plants.
could be a humidity/temperature thing. I grow in a greenhouse also and the humidity/temps can cause some funny things. if their yellowing, you might want to start using full strength nutes. Havent used hesi tnt complex, but thats what I did with my dyna-gro and it worked itself out.
New leaves are looking fine. Just the fan leaves on the lower parts of plants are having problems and are turning yellow with some strange black dots on them. Maybe it indeed has to do something with temp/humidity because i was experimenting with my tent setup for few days. And I was giving them less nutrients because I thought it was nut burn.
btw, greenhouses work great! This is my first grow in one and plants are loving it. Tall and bushy. Good Luck
One of my favourite breeders
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I can also recommend dutch passion seeds. Never had any problems with their strains. Orange bud is one of the best classic and easy to grow strain I ever had, and it looks/tastes great. Now I'm on the 8th week of vegging DP Euforia and it grows like crazy (even that I'm still a noobie and I made few mistakes at the beggining
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