Is this nute burn or heat stress???

[Beachwalker]

Im not seeing a heat issue or nute issue, i'd grab a scope though and check the underside of those leaves, maybe it's just the pic, but im seeing many little dots on those leaves.

^ agree w/ blitz, check for mites

 

[CannaCountry]

And yes, Walmart (maybe the other big box stores do as well) sells Alaska brand calmag...personally, I've used it and I think it sucks, but it worked enough when I needed it in a pinch...it's better than nothing.

 

[jellero]

I'm just not seeing temperature issues here.

As you see here, nitrogen toxicity normally involves darker green leaves. I'd do what Blitz said, Cal-Mag should darken them up if that's the issue. Can be a problem in flower though, so watch out.

that looks like root mites to me... i would add a little neem oil, maybe 1/2 teaspoon to a quart of water, add a little each day until they get the idea. spray leaves with pure water every day as well. now if i could figure my problem out. john

 

[Logan Burke]

That pic was an example of Nitrogen toxicity from Growweedeasy.com lol

 

[Blitz35]

that looks like root mites to me... i would add a little neem oil, maybe 1/2 teaspoon to a quart of water, add a little each day until they get the idea. spray leaves with pure water every day as well. now if i could figure my problem out. john

You sure? I think that's a typical symptom of dog urine being within 10 feet of the plant? This is a hard one! lol