Is this Light Burn?

[THSea]

I came home today and when I checked on my girls I found this.


And another...



I read somewhere that this may be light burn and wanted to know what you guys think. These girls are in ocean forrest soil with perlite and a pinch of dolomite. Under 1 600w hps and a few cfl's. I use the fox farm trio, typically with good results. I also add a micronute additive and occasionally a 1/4 tsp of Epsom salts. Ph is 6.9, but when I initially stick the probe in the soil, the needle jumps to like 8 and then back down to 7 and then after a few seconds settles at 6.8 - 6.9. They're under 24 hours of light

I am also having an entirely different problem with a sativa. The leaves on this one are curling like a claw, but it is otherwise growing like mad and looks very healthy. Here's a photo...

 

[Lofty]

hi THSea, a good way of telling if it,s lite burn is looking at the leaves furthest awy from the lite, if u can c a dif between the leaves near the and away from the lite, BINGO! the second pic makes it look like lite and heat stress, a pic of yr total set up wil help, explanation of air flow, temp etc.

if yr using a folier spray while the lite is on, that can cause it.

mor info, room pics needed.

 

[THSea]

The affected leaves are not just at the top closest to the lights.
My sapce is vented with two 8" inline fans. One of these at the top of the cab, and the other connected to my hood. I do not have an intake because I just leave the door open and use a 8" oscillating fan to blow the cool air in. If the closet is left open like this, temps are around 80 and peak at 85-87 during the warmest part of the day. If the door is closed the temps break 95, but I NEVER leave the door closed with my 600w HPS. If ever I do have to close that door, I unplug the HPS and just run the CFL's.

I don't foliar spray at all because of the spotting that it causes.

Here are some more photos, first of the leaves without the HPS on (much clearer) and then of my setup.



















Thanks for your help on this matter. It looks like it's getting worse so I hope I can get a handle on this soon. This is so wierd, I have been growing for 5 years and never had this happen. The only thing I can think of that's any different is that I'm using a 600w instead of 400w, and ocean forrest soil. To be frank, I'm not impressed with ocean forrest. I have heard people raving about it, but I don't think it's any better than the soil I bought from WallMart.

 

[Sinfuldreams]

How old are they.
Where on the plant is the trouble leaves?

Clawing can be due to over N.

OF is good.. but you need to add a lot of stuff if you grow Oraginic anyway.
Nothing wrong with WalMart Soil either!

Sin

 

[THSea]

They are 2 months old if you count the age of the mom they were taken from.

 

[10k]

I hope I can get a handle on this soon. This is so wierd, I have been growing for 5 years and never had this happen. The only thing I can think of that's any different is that I'm using a 600w instead of 400w, and ocean forrest soil.

Is that "stick it in the dirt" pH probe new too ?

Ph is 6.9, but when I initially stick the probe in the soil, the needle jumps to like 8 and then back down to 7 and then after a few seconds settles at 6.8 - 6.9.

Those silly meters are useless pieces of crap imnsho.
Get a decent digital pH meter or go back to just using a liquid test kit or litmus paper.
Do a proper soil pH test using litmus paper or a digital meter and see how that goofy ten buck soil probe reads in comparison, and then you'll know if you've been misleading yourself ever since you started using that pos soil probe.

hth

 

[Sinfuldreams]

10K got a VERY GOOD POINT!
Never worked for me.

Sin

 

[mr.niceguy]

PH WAY 2 HIGH!

PH WAY 2 HIGH!

no bro that looks like a pH problem...man i hate it walkin n my room 2 find some new problem with my girls.

to get an accurate reading of ur pH by the little pH meters, hanna is a real cheap one, pH 600, like 10 bucks on ebay, make sure u by the calibration fluid with it.

to measure ur pH, pour the water uve been waterin with thru the soil wait for it 2 drain and have a clean cup 2 collect it n, measure the pH, this is the pH of ur runoff. i.e. wut the pH is n the soil.

now wait 2 dry out and SLOWLY bring ur pH down 2 6.0-6.3 range. by adding STORE BOUGHT ph up and ph down, ull need an eye dropper 2 do this, take it slow 1-2 drops at a time, stir and let sit for an hour. come back and check ur pH, also make sure u swirl ur meter around n some clean water each time when checkin a reading, and dry it off before using again. write down how many drops u put n each time, repeat the process until u get 2 ur desired pH.

the reason u write it down is so u can just add the number of drops each time u refill ur bucket instead of havin 2 do this whole process over and over.