Uva/ Uvb supplement lights

So as I’ve stated in past posts new to indoor ( have grown incognito outdoor with some pretty good results ) I am in the process of setting up a grow room (4×6) in basement (kinda low head room can only get light to 6ft above cement floor but its all i got ) looking for a flower footprint of 4x4 (maybe bigger in future).
Trying to get it right the first time (well as best as an old fat noob can get ) have decided on my big ticket item (light) will be an HLG Scorpion rspec due to recommendations from @dbrn32 (thank you for being patient with me )
I’m still waiting for the assets to buy this light . I have lots of other stuff to do to get ready for when it shows up out front.

Some of those thing regard reading up to try avoiding mistakes and gathering information on different things to look for and things to avoid
So please don’t judge and be patient I have issues but those are my demos and I will leave it at that

SO my question is should I buy the hlg uva light bar for this light
I’ve read differing opinions
@dbrn32 kinda says it’s not worth it @Hellraiser uses one at 12/12 during flowering

I think while I have the funds I should get the add on won’t hurt
But if my money could be better spent somewhere else where ?

And what about uvb will a reptile bulb work ? I have a few t8 ballast and one 4 light 4 foot t5 high output
I could hang and get pure uv bulbs for (maybe can’t find anyone with any in stock)
I also know kiss (keep it simple)
So being a noob should I even worry
Just have read so much conflicting story’s
Thanks and keep it burning brothers


Definitely worth buying very nice light

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I have a t5 HO uva/b bulb and it has made quite a difference in trichome production.


I also use the uva30 12/12 on my 600rspec along with 2 2ft uvb fluorescent lights (GrowBright 2 Foot 1 Lamp High Output T5 & AgroMax Pure UV T5 Bulb – 2 Foot from htgsupply)… One on either side of the rspec.

Also… I use the HLG Flowering Initiator Far Red Bulb.
I use it… Turn on 10 minutes before lights out… Turn off 10 minutes after with light timer.

Not only have my buds been the most crystally looking and potent buds I’ve even had… Also thanks to genetics, properly controlled environment, listening to those with experience on here… But dense, beautiful, tasty, dank… I can’t explain my happiness in how my buds have been turning out… Sucks i don’t have anyone to share with… It’s all personal stuff and wife doesn’t puff.


No uv in either of my lights. There is some violet in one though.

Thank you
How long do you run the Argo t5
To try and save some money I thought about putting my high bay 4 foot 4 light t5 in beside the rspec and just run 2 Argo bulbs (if I can find them) just don’t want to far and screw things up

Ive got these coming there a UVA grow light on AliExpress

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Now yall got me curious about this too. Just any uva uvb light will do? I see @Aussie_autos ordered just some regular t5 fixtures and bulbs. Im curious how many of these id need in a 4x8 for it to be effective


I really like these but as mentioned you have to be careful using it



Is that just the bulb or the bulb and the light tho?

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I’m thinking I’d need something slim to fit in between my lights now and maybe 2 or 3 of these between my lights would do the trick? Either some small ones in between the lights or 4 big ones one by each door opening

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Just the bulb you have to buy a t-5 I believe it is. I was checking them out awhile back and put it on my maybe someday list on Amazon… I’ve seen a couple people using this one and said it really increases the trichomes


I’m thinking about these and getting 2 packs so 8 4ft lights in total then putting them in between the bars on my current light marked option 1 in purple in the pic above. Think this will be enough or would I need more or stronger lights?

Here is the other choice. Much higher wattage bulb. 54 watts compared to the small lights i just posted at 22w. Like I said not sure if wattage plays a role here but I assume 2 of these higher powered lights would be sufficient enough to provide the proper lighting to see change in Trichime production? These i guess are rated for a 4x4? Not sure how to read this chart

That says uv-c which is very dangerous for people


Good call. I know nothing about adding UV lighting to a grow but im interested. Seems all the agromax bulbs are sold out for “pure UV” i can only find 2 ft bulbs

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Same here
Some kinda government conspiracy
I still have time before my assests arrive so I’ll keep an eye out. Tag ya if I find any in next few weeks . Or if I can find a 24" t5 ho cheap.

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Yeah just read that it’s UVC
can’t use that .
Unless your trying to kill mold and stuff then must be very careful

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I run UVA pretty much all the time, many benefits other than more trichy buds, even in veg it increases cuticle thickness making plants more hardy, better able to deal with pests, stress, fungal infections.

I’ll also be using UVB for last few weeks of flowering to increase THC and terps.

Is it worth it? A one time investment of $150 for the HLG UVA30 that will last for years, worth it to me but I have everything else dialed in, have great lights, great environment, etc… My grow tents are not lacking for anything.

For many growers they may be better off putting that money towards better or more lights or other grow equipment, but if you already have lights capable of putting 1000 PPFD or more at your plant canopy and have everything else in place (good ventialtion, good temps, etc) than UVA and UVB can take your grows to the next level. Who doesn’t want more THC and terps?

Here’s some input on the subject from the good Dr Bugbee and Professor Runkle.

Be careful when buying UVA and UVB lights, some are good, some are not. If the UVA light you are looking at says “Blacklight” in the description then it probably is not a goof UVA light and is more of a blacklight made to light up those crazy colored posters, different spectrum and most likely to give off very little actual UVA. Want a good UVA lamp, look at HLG or ChilLED

Same with UVB, good ones and bad ones. I’d stay away from the reptile UVB lights as they emit very little UVB - don’t want to burn up those reptiles that tend to be pretty close to the lamps. Much better UVB options these days.

If I was going to add UVB, there are some I’d look at like the California Light Works UVB

Or the Migro UVB

Or the Solacure UVB

Have to be more careful with UVB though, only use for last 3 weeks of flowering and only a couple hours a day, and stay away from it when it is on as it can give you a wicked sunburn unlike UVA.


Thank you @Hellraiser much appreciated
Trying to start things out right .
Having the help of people on this forum is a wonderful asset
As things have changed quite a bit from when I started to grow
Bag seeds and miracle grow are with the dinosaur now .
I have done a lot of plant training because of it being illegal had to keep things low.
Now adays not worried about cops but thieves
So a new adventure into indoor where I can control everything
So that’s why I’m trying to take my time and start off right.
I know I’ll make some mistakes and spend money on stupid stuff but that’s part of the curve once I get everything in place might start a journal. Not the best at stuff like that so we’ll see
Again thank ya’ll and keep it burning