Any ideaa what this is and how to cure it

Couple of my plants have theese brown spots on them should i be concerned?
Anyone know why and how to get rid of them
Ph seems good 6.5
Ppm seems good 650 or so
Was using foxfarm nutes but switched back to Jacks 20 20 20
Heat 75
Humidity 65 to 75
Any input appreciated

Get your temp to 80 if you're using LED.

Can you explain what is wrong and why would i need to raise heat to cure
Im kinda thick so need things explained
Thanks

isolated blemish.
Temp is better around 80 under LED, or at least get the leaf surface temp up around 77.
They look hungry, Healthy but hungry. Is it time to up the EC on your feeding chart?

I had the same thing and switched back to my old nutrients no problems since. Jack's is not for everyone.
You should walk your pH down a bit, 6.5 is a bit high, I'd shoot more for 6.0-6.2 and see what happens.

Raising heat with LEDs will assist with transpiration due to LEDs not increasing Leaf Surface Temp (LST). Example with HID lighting usually you get a +2-3 °F hotter leaf even 24 inches away from the plants, with LED this does not happen if anything your LST will be 2-3 °F cooler than the air with proper airflow, this is why LED growers suggest 80 °F when lights are on.

What is your feeding schedule like? When you feed, be sure you feed to plenty of runoff.

I feed once a week and feed to some runoff will try to feed a little more

Am I the only one that sees a cal-mag deficiency?

I see a mag def that can be fixed with an epsom salt foliar spray.