UV-B 70W Metal Halide and 150W HPS Grow

[dagon420]

My first grow. Two plants under a 70W metal halide UVB reptile lamp from www.reptileuv.com and a 150W HPS.

They are grown in soilless promix. Fourth week of flowering. One is Afghan x Mazar and one is White Widow.

Here are their clones, rooted aeroponically.

And now in the clones in the veg room under a 125w fluorescent (the plant on the left was grown from seed on the windowsill, so its a little stretched).

Custom built from a Mastercraft toolshed

 

[rrog]

Love the setup Dagon. VERY excited to see you here at IC Mag. Great job on the stealth cab.

So how's the UV bulb working? In your opinion, how many plants could 1 bulb cover adequately?

 

[DiscoBiscuit]

 

[rrog]

Dagon,

You don't have enough posts that I can PM you yet, so I'll have to settle for a shameless thread hijack.
I think you might find this thread really interesting: http://icmag.com/ic/showthread.php?t=116431

 

[dagon420]

No, I do not think that one 70w bulb is enough. It really only covers the tops of one - maybe two plants. But I rotate the plants so it could be ok. I'm not sure if it matters whether its just the tops of the plants that get the UVB light or if it has to be ALL the flowers.

Maybe they will come out with a stronger bulb, but the real problem is the fact thats its a flood light. Would have to get a UVB fluorescent but I don't think they make them that powerful either. Best thing would be like a 150w UVB fluorescent.

Crazy thing is that the plants don't seem to mind the UVB at all. As you can see they are quite close to the MH light.

My next purchase would be this Eye Hortilux 400W blue bulb though. It is supposed to cover the whole spectrum UV, BLUE, RED.
http://www.eyehortilux.com/blue.html

 

[rrog]

Hey Dagon,

You might consider getting the EyeHort HPS with enhanced red. http://www.eyehortilux.com/superhps.html

When I looked at all of this, the HPS has a naturally high blue spectrum. Great for flowering. The HPS with added red handles the veg period well, though arguably not quite as well as MH.

I figured I was going to need more precise spectrum during flower so I went HPS. 600W for 3 plants made a pile of buds.

Regarding UVB, I'll get 2 lamps, then for 3 plants. You're idea of rotating the plants makes great sense.

 

[dagon420]

What kind are you going to get? MV? MH? or FL?

 

[rrog]

I already have the 600w HPS Eye Hortilux. Used in my last grow. My one and only grow, actually.

 

[dagon420]

What kind of UVB lamp are you planning to get? The MH from reptileuv?
They have a 160 and 275W MV too. But I think alot of the spectrum would be wasted (green light).

 

[rrog]

Dagon,

I had intended to buy 2 of the 70W MH UVBs as you have. Same unit

 

[dagon420]

Yea two of those are optimal in my opinion. But expensive. And you should probably shine the lights from the top rather than from the side (the way I did it). But with my HPS reflector in the way, it is a bit difficult.

 

[dagon420]

Do you guys think that I can still LST the tall plant on the left in the fifth picture?

 

[dagon420]

For all of you who don't know the correlation between UVB and THC production here is a study by Lydon et al. 1987.

Also, here is a review of the data that currently exists on the subject for anyone who's interested:
http://www.druglibrary.org/olsen/hemp/iha/iha01201.html

 

[*mistress*]

No, I do not think that one 70w bulb is enough. It really only covers the tops of one - maybe two plants. But I rotate the plants so it could be ok. I'm not sure if it matters whether its just the tops of the plants that get the UVB light or if it has to be ALL the flowers.

Maybe they will come out with a stronger bulb, but the real problem is the fact thats its a flood light. Would have to get a UVB fluorescent but I don't think they make them that powerful either. Best thing would be like a 150w UVB fluorescent.

Crazy thing is that the plants don't seem to mind the UVB at all. As you can see they are quite close to the MH light.

My next purchase would be this Eye Hortilux 400W blue bulb though. It is supposed to cover the whole spectrum UV, BLUE, RED.
http://www.eyehortilux.com/blue.html

nice garden!

run uvb w/ mh+hps.

sunmaster warm deluxe provides broad spectrum; good over all bulb. the neutral deluxe's are less pieces of gold, but have similar wavelengths of light. mixed w/ hps provides dense tomatoes. uvb only accentuates final texture of fruit, as documented. both warm and neutral have spectrums in uvb wavelengths, if not mistaken.

also use purple and red party lights to influence plants' flowering.

keep enjoying your garden!

 

[rrog]

uvb only accentuates final texture of fruit, as documented.

Not sure what that means.

Anyway, grow looks good, Dagon. I'm not sure on the FIM-ing. I would vote to top it, but I think you'd have to leave in veg longer to get some flowering branches started. But that's not an experienced opinion. Sorry

 

[*mistress*]

uvb only accentuates final texture of fruit, as documented.

Not sure what that means.

the added spectral influence of uvb bulbs may influence plants' production of glands on+surrounding fruit.
fruit/flower used liberally and interchangeable. basically, unimpregnated ovaries.
whether due to a protection response, and/or just liking uv spectrum, plants seem to surround flowers/fruit w/ reproductive glands; more than w/out added uvb-specific light.
this, in turn, effects final texture of flowers. ultimately want as much reproductive organ/appendage development as possible.
hope this clarifies. more tr.c.omes...

enjoy your garden!

 

[rrog]

This has been talked about occasionally. Not sure if there's documented increases in trichomes, but there is documented increases in D9 THC

I think UV-B supplementation gets a bad rap because people are using junk lights, not really UVB, often UV-A, etc.

That's why I'm so glad people like Dagon here are using a quality tested bulb. Tested to continue stated UVB spectrum for months. Many bulbs fade off in UV-B after some number of hours, but an operator wouldn't know.

 

[dagon420]

Yea and I'm telling you my 70W UVB metal halide isn't even enough. Some grows are using one 20W fluorescent and calling it a UVB grow. I'm not sure what lights they use in the Lydon et al. study but I think it would be some serious bulbs.

A lot of growers are scared of using too much UVB because they think it will damage the plants. But I'm telling you it won't.

Can you imagine UVB output from the sun on a hot summer day in equatorial regions? A plant would have nowhere to hide, it would be completely immersed in UVB. I can only cover well the top of one plant. A lot of these so called UVB grows aren't covering anything unless they are using like 10 UVB CFLs and I'm sure they are not. Plus like the one of the videos on www.reptileuv.com says, you cannot be sure of the output/decay of CFL UVB lights, thats why they do not sell them on that website.

I do like their 160W and 275W MVs though. They are supposed to have no decay for at least 12-18 months. What do you think RROG? Would it be of any use to the actual growth of the plant? I don't want to waste so many watts on just UVB. Thats why I got the MH. But will cannabis grow well under MV lights?

 

[rrog]

Yea and I'm telling you my 70W UVB metal halide isn't even enough. Some grows are using one 20W fluorescent and calling it a UVB grow. I'm not sure what lights they use in the Lydon et al. study but I think it would be some serious bulbs.

They had some foot candle calcs, I think.

A lot of growers are scared of using too much UVB because they think it will damage the plants. But I'm telling you it won't.

Can you imagine UVB output from the sun on a hot summer day in equatorial regions? A plant would have nowhere to hide, it would be completely immersed in UVB.

Exactly!

I can only cover well the top of one plant. A lot of these so called UVB grows aren't covering anything unless they are using like 10 UVB CFLs and I'm sure they are not. Plus like the one of the videos on www.reptileuv.com says, you cannot be sure of the output/decay of CFL UVB lights, thats why they do not sell them on that website.

My point exactly. Too bad, really. Set the whole UVB thing back for us.

I do like their 160W and 275W MVs though. They are supposed to have no decay for at least 12-18 months. What do you think RROG? Would it be of any use to the actual growth of the plant? I don't want to waste so many watts on just UVB. Thats why I got the MH. But will cannabis grow well under MV lights?

Hmmm. I'm not sure what the spectrum is for MV. I was thinking that the UVB MH you have really cranks out the UVB, though. I hear you on the more efficient wattage, though.

 

[dagon420]

Check out this link for info on the Mega Ray MV lights.
http://www.reptielenlampen.nl/MegaRay.htm
They are highest in green but they have alot of blue too and some yellow. No infared which is really good. They could be ok.

Also this website for comparison on different UVB lights out there and their characteristics. Check out the tables in the results section.
http://www.testudo.cc/

The sun puts out way more UV light than any bulb.