Sick Leaves....

Have you been letting the soil dry out a bit before you water or have you been giving water regularly not letting the soil dry out so the plant always has enough water?

they do not dry out very quickly....I am under leds ...THIS IS NOT HAPPENING TO ALL PLANTS JUST A FEW.....

How's your vpd?

Looking at one of those leaves in the second pic it almost looks like a phosphorous deficiency.

Really, we're just tossing darts at a board with the information you've given us. Or rather, haven't given us. Brittle leaves are a sign of too much Si in my experience. But who can really say without knowing anything about how they're being grown?

Seamaiden said:

Really, we're just tossing darts at a board with the information you've given us. Or rather, haven't given us. Brittle leaves are a sign of too much Si in my experience. But who can really say without knowing anything about how they're being grown?

Click to expand...

I am using HP pro soilless.....under 600w x3 LEDs,feeding GH 3 part....just did a test PH and it read6.6..on my reader...'

I think that pH is a wee bit too high. I'm surprised you're getting brittle leaves, I don't think the GH 3 part really adds all that much Si, and without additional Si in the mix, I'm at a bit of a loss to explain why the leaves might be brittle, unless you're describing the necrotic portions. In which case, whoever said beginning P- is likely spot on, because I do see that uneven pattern, starting at the leaf margins and working its way in, that can be indicative of a P utilization issue.

So adjusting pH may be the fix here, try dropping it into the mid 5's. The necrotic bits won't come back, but you should be able to stop it from progressing.

What are temps and humidity levels like?

temps are on aver 20-25c...humidity 40%

Not great, but not bad. Try adjusting pH downward here, see how the plant responds.

Humidity this time of year, depending on where your at, if your running a heat source then it looks more like a humidity problem 60% since you're not flowering is not out of line.
Could be a combination of the two heat and humidity with those 3 600w leds. Are you in a tent?
If so you need to find away to get all that heat out also.
Heat and humidity will crackle leaves faster than you know what, then if you have a fan in there also blowing all that unmoist air around, you'll dry them babies out quick