Is this light or heat stress leafs cunning

Temperature is at 75
Humidity 62
Grower choice light 720 at 50 percent power
3 feet away from plants
2 6 inch fans moving air inside the tent and 1 6 inch exhaust fan all controlled by grow hub by vivosun

No, in fact, temp works better with LED's at around 82F ambient canopy temp because infrared heat is lower with LED than HID's and can bring up leaf surface temps to the most optimal for photosynthesis (around 77F leaf surface measured with an IR thermometer gun).

Light stress with LED's usually first looks like a magnesium deficiency that is only at the top of the plant. That is, the top of the plant will have yellowing between the veins (interveinal chlorosis) of the leaves. The tacoing that is associated with light stress comes from the HID days because HID's too close to the plants would cause tacoing from the heat of the light, not necessarily the brightness.

So you'll have to look for other reasons if your PPFD is in check. One would be the affected leaves being located too close to a fan.

ec121 said:

No, in fact, temp works better with LED's at around 82F ambient canopy temp because infrared heat is lower with LED than HID's and can bring up leaf surface temps to the most optimal for photosynthesis (around 77F leaf surface measured with an IR thermometer gun).

Light stress with LED's usually first looks like a magnesium deficiency that is only at the top of the plant. That is, the top of the plant will have yellowing between the veins (interveinal chlorosis) of the leaves. The tacoing that is associated with light stress comes from the HID days because HID's too close to the plants would cause tacoing from the heat of the light, not necessarily the brightness.

So you'll have to look for other reasons if your PPFD is in check. One would be the affected leaves being located too close to a fan.

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So what would be your opinion

Looks like it may be the beginnings of Calcium Deficiency. Ca deficiency, can cause leaf tacoing, and I see a couple necrotic spots.

jimihendrix1 said:

Looks like it may be the beginnings of Calcium Deficiency. Ca deficiency, can cause leaf tacoing, and I see a couple necrotic spots.

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What is necrotic spots ? What do you suggest I do I gave them pure empsom salt and cal mag already in there feed

sinistergrow702 said:

So what would be your opinion

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Since different issues with plants exhibit similar symptoms and one has to go down a dichotomous key to distinguish one from the other, it would be helpful to know exactly what you're doing to get to the issue as quickly as possible, as none of us have the history on the plants like you do.

Things like:

What medium are you growing in?
Are you using dry amendments or bottled nutrients? What brand are they?
How often do you feed and what is the EC or PPM of that feed?
What is the pH of the feed?
Are you using RO water or tap water?
Do you ever give the plant straight water, or is it always fed with nutrients when watering?
If you're using bottled nutrients, do you feed to runoff?
What is the PPFD at the canopy?

ec121 said:

Since different issues with plants exhibit similar symptoms and one has to go down a dichotomous key to distinguish one from the other, it would be helpful to know exactly what you're doing to get to the issue as quickly as possible, as none of us have the history on the plants like you do.

Things like:

What medium are you growing in?
Are you using dry amendments or bottled nutrients? What brand are they?
How often do you feed and what is the EC or PPM of that feed?
What is the pH of the feed?
Are you using RO water or tap water?
Do you ever give the plant straight water, or is it always fed with nutrients when watering?
If you're using bottled nutrients, do you feed to runoff?
What is the PPFD at the canopy?

Click to expand...

They started in happy frog in a 1.5 gallon pot and transplanted 2 weeks ago in to a 5 gallon strawberry fields by fox farm
Nutrients are
Fox farm grow 10 ml
Micro 5ml
Cal mag 5ml
Hygrozyme 2.5ml
And epsom salt every 2 weeks
I feed Monday, water wendsday and feed again Friday and water Sunday and repeat
Ec is at 800-1200 its filtered water and ppm are around 1000 I give them 2 liters every feeding and watering
No run off
Ppfd is around 500

ec121 said:

No, in fact, temp works better with LED's at around 82F ambient canopy temp because infrared heat is lower with LED than HID's and can bring up leaf surface temps to the most optimal for photosynthesis (around 77F leaf surface measured with an IR thermometer gun).

Light stress with LED's usually first looks like a magnesium deficiency that is only at the top of the plant. That is, the top of the plant will have yellowing between the veins (interveinal chlorosis) of the leaves. The tacoing that is associated with light stress comes from the HID days because HID's too close to the plants would cause tacoing from the heat of the light, not necessarily the brightness.

So you'll have to look for other reasons if your PPFD is in check. One would be the affected leaves being located too close to a fan.

Click to expand...

Literally says it all

sinistergrow702 said:

Ec is at 800-1200 its filtered water and ppm are around 1000 I give them 2 liters every feeding and watering
No run off
Ppfd is around 500

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I don't understand what you mean by the EC is 800-1200 and the PPM is 1000?

Do you measure in EC or PPM?

In my opinion, you're better off feeding every single time you water at the appropriate EC and go until you get at least 10% runoff rather than doing a feed/water/feed protocol.

What is the pH of your feed?

ec121 said:

I don't understand what you mean by the EC is 800-1200 and the PPM is 1000?

Do you measure in EC or PPM?

In my opinion, you're better off feeding every single time you water at the appropriate EC and go until you get at least 10% runoff rather than doing a feed/water/feed protocol.

What is the pH of your feed?

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I thought you had to do both this whole time shaking my head people on here kept mentioning both so I started tracking both

ec121 said:

Since different issues with plants exhibit similar symptoms and one has to go down a dichotomous key to distinguish one from the other, it would be helpful to know exactly what you're doing to get to the issue as quickly as possible, as none of us have the history on the plants like you do.

Things like:

What medium are you growing in?
Are you using dry amendments or bottled nutrients? What brand are they?
How often do you feed and what is the EC or PPM of that feed?
What is the pH of the feed?
Are you using RO water or tap water?
Do you ever give the plant straight water, or is it always fed with nutrients when watering?
If you're using bottled nutrients, do you feed to runoff?
What is the PPFD at the canopy?

Click to expand...

You think I should do some water only feeding

Agree with everything @ec121 said.

but I want to add something.

Google Stephenson screen.
It will show you how weather stations measure air temperature and why..

Because it may well say 75f but you're probably lower due to the direct light heating the actual measuring device itself and throwing off the readings.

Had that been hps which has a stupid amount of radiant heat , you'd be 10 degrees out or more..
But since its LED it won't be way off, but off is still off.

Since you're already low on the temperature side, you should try and be accurate, simply shading those devices will do.

If you get your air temp up and your watering practices improved then I think your problems will go away.

P.S use EC, because there's only 1, there's different scales of ppm , so EC is more straight forward, since we won't need to ask what scale you are using.