SOIL Dried/crispy edges with yellow spots

[Sirsmokealot507]

My plants started showing yellow spots and crispy edges about a week ago. Here is a picture https://imgur.com/a/MlxI6 it almost looks like the light has burned them but that's definitely not the case as there is plenty of clearance. I searched yellow spots on the forum but this looks slightly different than what I'm seeing. Please help. They're being grown in soil with a few small rocks at the bottom of pot to help keep roots from getting too much water and being fed with Fox farm nutes under a hps light.

https://imgur.com/a/MlxI6

[GRAND]

Looks like nutrient burn, real bad, also maybe nutrient lock out. check your ph levels and check your nutrient level. Good luck my friend!!

[Canuck147]

Looks like bugs to me - look under your leaves

[St.buds]

Do a flush with flora kleen or something like it then cut nutes n half and definitely look under leafs and in soil everywhere good luck

[D.A.A.S.69]

Looks like PH, out of whack to me and maybe some bugs also.

[Dagmar]

PH problems? Do you use CalMag ? How about wind burn... do you use fans on high blowing directly at you plant?

[Sirsmokealot507]

No fans. They were outside and are now inside due to cold weather coming so possibly bugs but I'm leaning towards nutrient burn. I'll get a pH reading in a bit. Thanks for the help guys.