HALP! CMH lights- what is going on?

[Thetinman]

have been growing for awhile now. But, ever since I moved to California, this is almost impossible.
Grow room is complete with everything you could imagine. But these seedling will NOT GROW AT ALL. Plants stay stunted or simply yellow out.
Keeping at 80°, 60-70 rh (like 38% humidity) dual 315CMH. LUX is presently at 10k+. Go ANY higher OR ANY lower, yellow out in seconds.
The humidity where I use to live was crazy, The South. Never ever had any problems like I have had here. Always used HPS for whole grow, no problems.
I have spent over 25k and 5 years to build this stupid thing and I cannot tweak it any better.
So i am reaching out and hopefully there are some answers out there....

 

[TripsRabbit]

Start seedlings under regular florescent lights, a cmh is too strong for babies.

 

[MIMedGrower]

I had to keep my 315 cmh 4 feet over seedlings in a 3x3 reflective tent or they would stress bad.

 

[Thetinman]

I am trying to figure out the correct lux. Do you happen to have a lux meter? Now I have pulled the light up before, the seem to do well, BUT will stretch ridiculously.

 

[Thetinman]

The Lux is around 10k. At 4' from tops. But there are 2 complete lights spaced 2' apart for bulbs.

 

[MIMedGrower]

The Lux is around 10k. At 4' from tops. But there are 2 complete lights spaced 2' apart for bulbs.

sorry no lux meter but with twice the bulbs need more distance. Got any pics?

 

[Frankster]

Yea, I agree back it off. I'm using light right now on the seedlings and using like 30% light. I got them acclimated by putting them in the tent under napkins at first. but I try and give some light at breakout.

they green up in hours after husk is dislodged.
Lets see some pics please. Are you working from seeds or cuttings?

 

[Thetinman]

Ya, getting harder an harder. Yes lights are at 4' exactly...

 

[Snaggleroots]

You can buy a simple analog meter to see what is hitting them.They cost less then 5 bucks.Seeds or fresh cuts like it above 500 but under 1000.Theyll try to get away from it if its too much and theyll try to go to it if its to little.

 

[Snaggleroots]

looks like the went up to like 15$ on amazon

 

[MIMedGrower]

Ya, getting harder an harder. Yes lights are at 4' exactly...

They look fine even a bit stretching for light.

 

[Thetinman]

Ok, a single 315cmh produces 6k at 4' exactly. Dual hiked up 5'4" now produces 6k also. Wow, 5 and a half feet. Appreciate the lux info. Gives me something to go by.

 

[Thetinman]

We will see....

 

[Frankster]

They look fine even a bit stretching for light.

I concur, I would be aiming somewhere in the 20-30k zone, they look like they are hardened enough and can handle it. At least for a few hours a day, then see how they respond to it.'

They look like they are expending energy stretching, so dial it up some, harden them more and more.

 

[Thetinman]

20 to 30k??? They fry at 12k

 

[Frankster]

You can buy a simple analog meter to see what is hitting them.They cost less then 5 bucks.Seeds or fresh cuts like it above 500 but under 1000.Theyll try to get away from it if its too much and theyll try to go to it if its to little.

You can actually download a meter that's much easier and cheap from your cellphone, if you have an android.

 

[Frankster]

20 to 30k??? They fry at 12k

I think were talking different lingo maybe. footcandles, lumens, lux... plus everything's different, and I'm not familiar with cfl measurements, actually. I would say go up to half of your full strength, or just under....

 

[Thetinman]

Analog meter? Are you talking par? I have a lux meter. At 6k lux, you are looking at 1900 par. Lux meters are just as much...

 

[Thetinman]

You can actually download a meter that's much easier and cheap from your cellphone, if you have an android.

Dude, they are notoriously inaccurate. This little meter seems to work well. But no one seems to own one! Haha!

 

[Thetinman]

You can actually download a meter that's much easier and cheap from your cellphone, if you have an android.

If you use CMH lights, at 4' from light, what is your analog meter read? I can probably do the math...