Growing with uv-a and led spectrum ratios

Hi all,

So im going to have customized t8 grow tubes made (im not pushing them on here yet so dont worry, lol)

The big brand led lights use a spectrum ratio of 3-1, 3500k:6000k, and they sprinkle in some 660nm red lights also.

I’m thinking of using this same spectrum, and adding a small amount of 365nm uv-a to the spectrum. The spectrum ratio would be 12:4:2:1, 3500k,6500k, 660nm, 365nm. It doesn’t cause any plant damage, but you will need to wear glass when you’re working with your plants, which we should all be doing anyways.

If you look it up, UVa will add to trichrome growth. I added a blacklight (also UVa, usually 385nm) tube to my other tubes and had solid results. I also used live soil for the first time, so its anyone’s guess.

The question is to UVa or to not UVa? The cost on the tubes is the same.

3 Likes

@preybird1 Would be your huckleberry for this info…

1 Like

Indeed, im pretty sure @preybird1 answered the last time I talked about these type of t5/t8 led tubes.

The other questions would be ideal spectrum ratio, and whether upgrading to ip65(almost waterproof) fixture is worth it.

4 Likes

I just purchased and am running the HLG UVA30…just in the am to mimic the intensity of the sun. From what I’ve read and seen from @Hellraiser…we wont be sorry. Trics and a ton of them.

And hell, a built in tanning booth ain’t a bad gig either…just kidding.

4 Likes

Whats up guys?

3 Likes

vegetative period of your plant’s life cycle. It’s light is 80% 5500°K, 10% 460nm blue, and 10% 380 nm UV. Never did a t8. This is what i use i really like it.

3 Likes

This is what I used https://www.amazon.com/dp/B074N26GJT/ref=cm_sw_r_cp_apa_fabc_SV6N3V8ZE53Z4BTC993M

It worked well (I think). Still, UVa only makes up like 3% of the light spectrum, so I was thinking of trying to mimic that.

2 Likes

Are you trying to do a full cycle light?

3 Likes

Yes, both Veg and Flower. I think I looked at fluence and they used the 3:1 ratio 3500k:6000k

2 Likes

Ahh i posted a veg sorry

2 Likes

its ok. still, 3 congruent questions that I have

  1. best general spectrum
  2. adding uv or ir good?
  3. is going from ip20 to ip65 (almost waterproof) worth it. Cost goes up 20%.
1 Like

what kind of lights are you using? I read elsewhere you make your own?

1 Like

Here is what my tube looks like so far btw.

I can basically do whatever spectrum Id like.

2 Likes

Seen a few of those can change spectrum :v:t2:

2 Likes

Yeah I can do whatever I like. I think I do a “general spectrum” for both veg and flowering.

These are 42w, they would retail at $30 per tube, online/amazon they would be in the $20s.

1 Like

Seen those on eBay can’t recall the price…
Might do that at some point I am going to do ir far reds, like that idea

2 Likes

So you like the UVa and you think I need to add some IR far red? noted!

On ebay this is close:

Prices are similar, but my lights will have UVa…also a realistic spectrum as well as better branding and marketing. The english on this ad is very sub-par.

1 Like

Im using 4x full spec 170 watt boards. Then in the corners i use 4x hlg v2 elites.
Here

I love these little lights.

3 Likes

Very interesting.

What do you think about the addition of UVa or IR?

Also, do you think waterproofing is a necessity? I noticed you mentioned waterproof lenses.

2 Likes

I would add them. I havs a foshe aeries and it has over cast adjustment. And my seedlings are under uv also. I like it.

3 Likes