Do/Should I add UV?

Lets jump right into it...
Setup:
5x5 gorilla shorty
2 phantom 315s with flange kits vented out
.......
So this is where I wonder if I will have an issue soon.. I was just informed that the lens will filter out some of the great uv rays of the cmh...(I do not have any specific number or percentage sadly)... will I still be ok

Or, should I buy an led (open to suggestions on other ideas) to add in for uv?

Or will I be fine?

I am running with glass because the tent is only 6ft and being cooled I am under the impression that I will be able to grow them taller since the heat is being pulled and they shouldn't get burnt.. Im hoping to be able to get to around 10" away from the glass safely ,if need be..but still learning

Thanks for your help

I personally view UV more as a supplement than a necessity. You can grow quality flowers without the use of UV being present. If you really feel the need to add UV, you can get a T5HO fixture and run an Agromax Pure UV fluorescent on a timer, or get an Agromax UV A bulb and run it along side of the CMH on the same timer. Its the UVB you have to keep an eye on.

Keeping your temps down takes priority over whatever UV spectrum is lost through the glass. Used to run a Solistek 10k MH with UV and tried running it without the glass but ended up putting the glass back in as temps were soaring. The bulb burned out after 6 mo & was replaced with a hortiluxe 600w hps.
As an alternative I added a T5 alongside my 600w hps fitted with 2 Agromax UV bulbs and 2 eye hortiluxe full spectrum plus UV bulbs. The T5 works great for finishing plants late in bloom phase. It makes for super dense tight frosty buds. Also seems to speed up ripening just a bit. The fixture itself was fairly cheap but the custom bulbs cost more than the fixture. Adding UV is great but as Red says it's supplemental rather than essential.

Thanks for chiming in guys, I have to say that "more as a supplement than a necessity" is a perfect way of saying it. thanks for explaining it like that.. I will have to read up more on the uv light and the qualities it can bring to the plant.. And I like the idea you tossed out Drysift on how you solved your problem the way you did by adding the extra lights.

BigGreenHulk said:

Or, should I buy an led (open to suggestions on other ideas) to add in for uv?

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Just so you know...led lights do not produce UV.

Most people worried about UV just add MH to HPS in flower.
JD

Maybe try running them without the glass and exhaust above the lamps with good circulation fans blowing between the reflectors and canopy.

Unless they are single jacketed bulbs and require the glass for safety.

I want to add that I was able to grow equal and even more frosty and potent flowers under my air cooled 600 hps in glass sealed reflectors as flowers grown under a Phillips 315 cmh in an open vertical reflector.

I agree with the above growers that other variables are more important than added uv.

If you grow shitty weed without UV, you will still be growing shitty weed with it, while maybe growing some skin cancer.
Nearly everything is known about the cannabis plant. What ph range it likes at different stages of life, recommended food levels with and without CO2, proper temperature and humidity range to keep enzymes active and transpiration going strong.

But, people want to find shortcuts....
If you can find a shortcut for controlling RH and temperature actively, it is 99% likely that it is just because of the season you are in.... trying to repeat everything exactly the same way, 6 months later will not have the same results. In hindsight, saving power on lighting that you can use for heating and cooling, although costing the same when added, will produce better weed.

Size your grow to the room, insulate everything and you won't be spending money climate controlling a volume of space you don't need.

as far as how far from the glass, use your hand. if its hot its too hot lol. put a fan blowing over your tops. and if you can bump up your hood vents..... but that glass is going to save your whole tent 5 degrees.
some people use uv for last minute stressing that supposibly adds trichs due to the need to protect itself.
as alot of people said it wont "increase quality" so to speak. just add the potential to induce that stress factor.
leds dont emit uv, unless you specifically incorporate uv chips into your build.
and again go to your hydro store, or a few. and ask how many of the 10000k bulbs they sell..... you get all sorts of funny answers but they all lead to they dont sell them, and they just sit there.

where im leading to, is will you even be able to see the difference or are you just trying to get the best quality product? if the later, ditch the fancy stuff and focus on getting your grows down..... your equipment is fine. you just need to get comfortable using it.....
all in all the ppfd on most hids cmh are very close to leds, its just the extra heat and electricity.... but cmh are great lights and are highly used by like every one.... professionals and hobbyists.... at least get your moneys worth before you move on, or your going to be mad at that perfectly fine 300$ pos on your floor. because your only excuse is going to be that your leds are more efficient.

thank you everyone for the bit of input.. helped point me in the right direction from here.. much appreciated

The CMH bulbs still put out UV, they're easy to cool without air cooled reflectors. I've been really disappointed by LEDs, weed grown under them is lacking... Something. Every grow under 315s made me really happy, my LED buds just don't impress me.

Psyphish said:

The CMH bulbs still put out UV, they're easy to cool without air cooled reflectors. I've been really disappointed by LEDs, weed grown under them is lacking... Something. Every grow under 315s made me really happy, my LED buds just don't impress me.

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do you possibly have pics from past grows? id love to see what you mean?