about the UVB light!

hello today iam going to buy rapti glo 10.00 its t5! so how long i should run it each day!

now i have 4x30w cfl bulps, and iam growing 2 autoflowering strains bubelicios and big bang!


Sorry about the mistakes, english isnt my first language!

How long should you run your light? Autoflower strains are best at 20/4 and 18/6. Personally im running mine at 20/4.

I think he is talking SUPLIMENTAL uvb?????
My plan from reading is to turn them on
a few hours a day.
Ill probably start with three or so and go from there. As soon as I convince the wife we have to have them by law or some other excuse.
Other than that I have no real answer so Ill shut up and wait with ya.


**H@Ck ALLeRt**
Any info I give is based on what I would be comfortable doing.
Please get other opinions.

In nature plants don't live in plastic buckets but at my house they do or they get the f**k out.

but can i run uvb light 18/5

You are not running only uvb are you?
From what I understand
You use your regular light as usual
but add uvb for a while during the light on period
Again im only repeating what I have heard

**H@Ck ALLeRt**
Any info I give is based on what I would be comfortable doing.
Please get other opinions.

In nature plants don't live in plastic buckets but at my house they do or they get the f**k out.

Ive never used UVB lights,but ive looked into using them.
I think they are only supposed to be on for about 6 hrs,and for 15 minutes each of these hrs.
Obviously you would need a separate timer.I found this link for you to have a look at.GL.
http://bigbudsmag.com/grow/how/article/get-more-thc-your-medical-marijuana-plants-using-uv-light-august-2012

Good question.
How about putting the UVB light further while increasing exposure time?
Would it have the same effect?

Turning it on and off many times a day would greatly reduce the bulb's life I expect.

The problem with any reptile UVB lighting is that they have very little effective penetration. They are only effective to 18 inch's for our use (the effective usable UVB has dispersed to ineffective levels over 18" away). Most reptile "tanks" are less then that in height for just that reason!
I've run side by side's and have found that the cost to benefit ratio is not worth it. (Run only the last 2 weeks of flower for the best results - tends to "burn" plants otherwise!)
Now if you have a 400w HID ballast and get a 400w Mercury Vapor bulb. Your result is better, but still not worth my time or electric cost to the benefit. If you elect to try this. You should use a "wing" style light fixture as the glass in an air-cooled hood will block much of the UVB (glass is designed to)! Same is true for running your MH bulb the last 2 weeks of flower for the same idea (extra UVB and yeah, it does have an effect and will not change your electrical cost).

The choice to try is yours....But now you have some actual hands-on advice.

P.S. Yes, Charface is correct! it is used as "supplemental" lighting.

If you must uv-b is good for the last 2-3 weeks of bud, apply just before harvest to finish off the buds, I prefer the sun, does a good job, even in winter, just longer,
otherwise the UV-b will fuck with your eyes at worse blind, at best coke bottle lenses

Dr. Who said:

P.S. Yes, Charface is correct! it is used as "supplemental" lighting.

Click to expand...

Im also fast to jump on the bandwagon.
Its weird, weed is so good already
yet I dream of hanging an octopus
of reptile lights in an already crowded space. Oh well, at least we have heard
some first hand data. Probably not worth
the additional complication at this point
for me. :beer:



**H@Ck ALLeRt**
Any info I give is based on what I would be comfortable doing.
Please get other opinions.

In nature plants don't live in plastic buckets but at my house they do or they get the f**k out.

Just to add my $.02 I have one 26w reptiglo 10.0 that I run the full 12 hours the lights are on, about 3-4 inches from the canopy (as the levels of uv-b it produces are nowhere near what outdoor sun exposure is, I see no reason to turn it off as I see no way of overdosing with a bulb that small) and I've noticed that the buds closest to it are noticeably frostier than the buds furthest away. (Also I've noticed that buds closer to the 6500K bulb have a similar increase in trichome density when compared to the buds closer to the 2700K bulbs, my guess is that it is from the extra uv-b the 6500K's put out)

Im not much of a numbers guy.
Are the plants already getting a full dose of light or is it possible that the uvb is making up for a lack in the areas where
its on.
Meaning, if the plant already had sufficient lighting would you still see this
major improvement.
I hope that you understand my question.



In nature plants don't live in plastic buckets but at my house they do or they get the f**k out!

Yeah the plant is getting plenty of light, 85w 6500k, 68w 2700k, (2x) 65w 2700k, 40w 2700k, and 26w 10.0 uv-b, over 300 actual watts for one plant and lux meter measures 20,000-50,000 lux at all areas of said plant. So definitely enough light, and the plant is frosty everywhere, but the areas closest to the uv-b bulb and the 6500k bulb are definitely the frostiest.

I use a 26w UV-B bulb in the last 6 hours of day in my flowering room. It promotes resin production on your flowers.

I run my UV lights for 15 mins of each hour from hour 3-9 of lights on. It is a noticeable difference, esp on already good quality strains.

Ace Yonder said:

Yeah the plant is getting plenty of light, 85w 6500k, 68w 2700k, (2x) 65w 2700k, 40w 2700k, and 26w 10.0 uv-b, over 300 actual watts for one plant and lux meter measures 20,000-50,000 lux at all areas of said plant. So definitely enough light, and the plant is frosty everywhere, but the areas closest to the uv-b bulb and the 6500k bulb are definitely the frostiest.

Click to expand...

Excellent. Thanks.


In nature plants don't live in plastic buckets but at my house they do or they get the f**k out!

I wonder if some run them intermittently
due to heat?

In nature plants don't live in plastic buckets but at my house they do or they get the f**k out!

It's possible, I find that since the bulb is so small it's not a problem. I switched out a 65w 5500K to make room for the 26w uv-b 10.0 and my grow box temps dropped 6 degrees, but I suppose that's to be expected. It's worth while to note that CFL reptile lights are designed to have a high uv-b output but aren't designed to be used as a heat lamp (Which is what incandescent reptile lights are mainly for), so I find the heat output is about the same as any CFL of comparable size, maybe slightly higher but nothing extreme

I would be hesitant to switch them on and off too often throughout the day as that absolutely wreaks havoc on CFL's lifespan