HLG UVA XL Yay or nay?

I am thinking of pulling the trigger on this light since it would be on sale until the 22nd of the month.

Any thoughts or feedback on if it is worth the investment for UVA at all?

I am going with the XL since I typically grow 3 plants in my room at a time.

Any feedback is appreciated!

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I’m a proponent of adding UVA. Huge increase in trichs between plants under UVA vs those that aren’t given supplemental UVA.
I have seen the difference with my own eyes with clones cut from the same mother and there’s plenty of “real” science to back up the assertion. Much more real science behind UVA than 48hrs of darkness before flip, yet people continue in that practically fruitless practice.

I have both HLG and Forever Green Indoors UV supplements in separate tents and I prefer the FGI.
HLG sources their UV lights from China, same as FGI (In the same factory I think!). Other HLG products are assembled in Ohio, this product is not.
Both are quality lights and you can’t go wrong either way.

HLG 350R with HLG UVA30 and FGI Far Red bars -

HLG Scorpion Diablo with FGI UVA and Far Red bars -

Thought I had one of the big set up with the FR on too but apparently I don’t!
But trust - they work! LOL!

Happy Growing Everyone!!!



Ill check out the pricing on the FGI.

Do you have the 730?

I have 2 HLG 135s and 1 Chilled X3-330 so either way I need to mount separately.

I have a UVA-30 mounted between two HLG 260 Rspect lights. And a UVA-30 XL side saddle with my HLG 350R.

3 x 3 Setup.

UV Only.

2 x 4 Setup in seedling veg mode.

I don’t know - what is it? :rofl:

The UV rides side saddle with the 350R, same as @Blastfact . The clips are drilled through and bolted to the heat sink on the Diablo. Works beautifully!

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So is there a difference between UV vs UVA? Also what about the far red that @Tylersays mentioned?

Now that I’m looking in so confused haha

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I use UV and UVA kinda interchangeably, if that’s a word LOL!
UVA is for plants, UVB warms reptiles and UVC will kill us all in no time! LOL!
Spent enough time bent over in the tent under a UVA and you’ll be a true “redneck” - you can feel it burning after a bit.

Far Red is a whole different ball park altogether.
It triggers other responses in plants and can be used to basically switch certain processes pretty much instantly in a plant. Red and Far Red are much more experimental.
I wouldn’t mess with them until you’ve got a grow under you belt.
It can get deep! LOL!

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Makes sense. I will check out and do some research.

I have a few grows under my belt and I am perfectly happy with how they are coming out, I just was looking to see what I can add to make it better, but I will start to do some research before just diving in.

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I added the HLG UVA to a Scorpion Rspec the last 2 grows. I won’t be running it next grow. Maybe I ran it at the wrong time, too close, too many hours or whatever, either way I have to learn more before I consider turning it back on.

Yes, I saw an increase in trichs right away, which I thought was great. However, over two grows running five different strains I had shorter flower periods and smaller overall harvest than I expected. Seemed like the buds were finishing when I expected them to be bulking up for another week or three.

Too many great growers here who use them so I’m sure they would benefit if used correctly. Just sharing my personal experience with adding/using a UVA bar, apparently incorrectly in my case.

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Sorry for the late response. By the time I saw this post yesterday I was in no condition to respond after a 4/20 day full of smoking the last of my real Colombian Gold plant grown from 1975 seed. The real stuff makes you see colors, tracers, time slice, slow motion and other mild psychotropic stuff. Sooooo much better than all this new fufu bred up crap weed. Hope everybody had a great 4/20. I damn sure did!

To answer your question. UV has three spectrums. UVA which is very mild and weak. UVB is much more harsh and in fact is what gives us for example sunburn. UVC which is down right dangerous and will kill us and every living thing on earth. UVC is filtered out by our atmosphere as is part of UVB at the far left end. What we are looking for in UVA is the amount of UVA we can produce with the cumulative effects of less UVB at the very far left end of the spectrum as it crosses over to UVB. This aggravates our plants and makes them produce there own sun screen/protection in trichomes. UVA is the easiest and safest UV to produce with leds. UVB is much much harder to produce with leds and when produced with leds the leds go bad much faster. There are UVB fluorescents and other types of lighting. But the over all production is low and they stop producing usable amounts of UVB pretty fast. UVB can be dangerous and expensive to use. UVB use to be used in hospitals a lot in the old days to help kill airborne pathogens. It was very common to find UV lights in rooms before there was air conditioning in hospitals when they use to keep the windows open all the time and had quiet zones all around hospitals. UVB lights were in fixtures above the patience beds aimed at the ceiling and were hard mounted so they could not be aimed at anybody in the room. With UVB if you get it in your grow tent the amount of time it can be used in your grow environment is far less than UVA. So maybe 2 to 6 hours max! for UVB while UVA can be ran 10 to 12 hours during the flower cycle counting on cumulative effects.

Far red is more about putting your plants to sleep much quicker. While red light from around 640nm to 700nm aides in growth and structure development. 700nm to 750nm red is about the Emerson effect and other hormonal effects. All this really far red stuff is new in the horticulture world. While all the UV info has been known about for well over a 100 years or better. I haven’t jumped into the far red area yet and own no lights that claim to operated in the 700nm to 750nm sphere of operation. But when I bought my PPFD meter I went ahead and bought the Apogee MQ-610 ePAR meter so when the time to jump in to far red happened I would be ready.

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I run my UV’s the entire grow in conjunction with the main light.
The sun doesn’t turn on UV for just a couple of hours a day - if you see the sun you’re basking in UV rays!
Far Red will switch the plant from “day” mode to “night” mode in a matter of minutes vrs the 2 hours or more it takes the plant to naturally make the switch - yes the plant “grows” in the dark. But it’s all internal processes and less external. I run my FR about 10 minutes in conjunction with the main and UV at the end of the lights on period and it runs for 10 minutes after the main and UV go dark.
In the morning you use “Deep Red” - the visible part of the red spectrum, to wake the plants back up again doing it in minutes instead of an hour or more.

To induce the Emerson effect you run them both simultaneously WITH the mains and UV.
That’s where it gets way more experimental.
If used correctly the combination can cause extreme vertical growth and it also induces the plant to produce larger, broader leaf structures. Which “Could” lead to larger fruit/buds. It’s just a matter of finding that sweet spot and is far from a known or exact science at this point.

Emerson effect aside, if used correctly as stand alones, the Red and FR can give you an additional 17% of “growing” time through flowering as you can flower your plants on a 13/11 cycle. Some 100% indicas can even go lower on the dark period as some strains can naturally flower at 13/11 anyway.
It can also chop up to a week off the flowering period too.
Increased light period everyday = increased growth and a shorter turn around across the board.

This is a pretty simplified, but informative write-up on FR and Red.

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@Tylersays @Blastfact

Thanks for the info! Unfortunately I did not partake in any activities as I am in the process of switching careers so I need to be clean :(.

I will do some research, it looks like the UV lights are out of stock, but I am going to double check.