drooping leaves after about 13 hrs of light????

[kctats13]

ive been vegging 2 og kush clones for 3 weeks now. plants are about 16 inches tall. im using kelloggs soil with botanicare liquid plant food. theyre in 1 gallon pots. Im using a 600 watt air cooled hps in a 2' x 4' grow closet. light is on an 18/6 cycle.
the plants are growing great for the most part. the color looks great and theyre growing about 3 inches per week.
the problem is after about 13 hours of light the leaves start to droop. and by the 15-16th hour theyre drooping bad!
but as soon as the light turns off then back on 6 hrs later theyre up and doing great.
then today i checked on them after about 10 hrs of the light being on and they were completly slumped over! the stems were bent over and it looked like they were dying.
then about an hour later when the lights turned off they came back up again....
is there a such thing as too much light??
what might be going on?
ive been reading and searching but cant find any one else with the same problems.
any help or suggestions would be appreciated.
Thanks

 

[UKgirl420]

when are you watering them ?

as plants tend to droop when thirsty and overwatered eace:

 

[UKgirl420]

also have you any pics ? they would help eace:

 

[ozzydiodude]

What are temp reaching at the time drooping starts? What is water sch?

 

[kctats13]

Im watering once every morning. I used to water every other day but now that the plants are bigger the soils been drying out daily.
The temp is around 75-80 when they start to droop.
Ill take some pics when i get home from work.
Are 1 gallon pots too small for a 16" plant?

 

[leafminer]

1 gallon is not too small, I have a Black Domina clone in a 1 gallon pot and it is 2ft tall and growing like mad.

Sounds to me as if your plants are getting too much radiated heat from the lamps. It's not the ambient temp, it's the radiated IR from the lamps, probably.
And, I have to say, 3" per week seems on the low side especially with that much lighting. I usually get at least 3/4" to 1" per day at that size.

You don't mention ventilation. I can tell you this: without good air movement you WILL get lamp burn.

 

[kctats13]

for ventilation i just have a 50cfm fart fan. i figured it should be good enough since the closet is only 2'x4'.
im kinda stumped about the whole thing. they look better today but still drooping quite a bit. all my grows have been with ebb and flo hydro and have went great.
i would of thought soil would be easier but it seems like theres more things that could go wrong.

 

[the chef]

Just a guess your getting to dry. I haave had some plants with soil i'd water almost twice daily but i did things a bit diff. I kept a 24/0 light schedule. I had a plant when the lights came on her bottom half was rigid but the top half was limp and bent to the side of the plant. A better watering regimine and 24 hrs light, don't know if that helped or not but my girl got back to shape in no time. Maybe just a bad case of dehydration as your temps are conastant..........whats your humidity? A humidfier might be what you need.

 

[kctats13]

my humiditys at 25-30%

 

[the chef]

Uh huh i thought so. A humidifier is a good answer. 30% in my estimate is way to low. Some shoot fer as high as 70 but you have to watch out fer mold issues. Shoot fer around 50% and that should help your ladies along.