What’s goin on with the leaf tips here?

[Pyper]

We’ve had some trouble lately. Power was out for two weeks, during which time I just keep them alive as best I could. This one—in photo—is the best looking of them, but is now showing burning (?) on the tips. I did just transplant it, and it’s now closer to the light. 600w LED full spect. Light is currently 30 inches about the canopy of this plant. I got three slightly younger (by a week) autos that are looking fine, but they missed the brunt of the power outage.

what’s the issue and how would you remedy?

peace

[CaptainWiese91]

Pictures in normal light would help.
info about grow would help at lot.
medium - Ph levels etc.
And what lamp you are using would help a lot. These 600w is that the real output of wattage ?

[Pyper]

Growing in this: https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

18 hours on, 6 off. Don’t have a ph meter yet but have been using distilled water. No nutrients/feed given yet—just happy frog soil. This girl hit soil about a month ago, but for two weeks or so we had no power. I did best I could with available light (see my last post). I just moved her from a solo cup to this 2 gallon bucket (which sits higher—hence my light burn theory?)

normal light photo uploaded

[JeffInCanada]

I think that it's going to be ok. I would just keep dong what you're doing but ensure it gets the right amount of light and watering. I have had those first few sets of real leaves get looking a bit rough before similar to yours, went through the same worry. The plants grew out of it. Keep a smart eye on it and don't do much drastic like overfeed/ water etc.

[dilvish]

Yup ... need way more info if you want a proper diagnosis. On first glance I would say a nutrient burn. when seedlings don't get enough light they tend to store nutrients. If you add more and the lack of light hasn't changed, you get a burned look on the leaves.

For now just make sure they are getting plenty of light (lower it to about 24") and are getting good properly PH'd water. Keep an eye on the heat and humidity and just let em go for a week. If it persists then try something else or look for more advice.

[Pyper]

Heat between 68-75, humidity around 50. But again, due to the storm, these numbers have been weird.

[PeterMatanzas]

It's a nutrient burn, but that nutrient is probably there and is locked out by a pH problem. Not only are the tips burnt, but the leaves have an accordion look that could be diagnosed as a zinc deficiency. But there's zinc in that soil but the plant wants pH below 6.5 to readily absorb zinc.

The picture below is Nebula's and is shown in the zinc deficiency discussion. Your leaves aren't that yellow, not yet they aren't. Notice how the leaves in Nebula's picture have an accordion look.

[Rwise]

Pure distilled water should be neutral with a pH of 7, but because it absorbs carbon dioxide from the atmosphere, it's actually slightly acidic with a pH of 5.8.

What is the pH value of distilled water?
5.4 to 5.7
Normal saline and distilled water had pH of 5.4 and 5.7, respectively.

How do you neutralize distilled water?
If one leaves distilled water exposed to air for 24 hours, a pH between 5.5 and 6.0 can be expected. To neutralize this acidity, it is sufficient to boil the water for 5 to 10 minutes, so that it releases the dissolved carbon dioxide, bringing the pH very close to 7.

Also there is nothing in distilled water for the tester to measure, it would need additives.