• Here is a link to the full explanation: https://rollitup.org/t/welcome-back-did-you-try-turning-it-off-and-on-again.1104810/

Cooled Hoods or Not

dbdweller

dbdweller

Active Member
What i would like to know is not the basic about closer and heat but:

An Hps does not put out UV so the glass has no effect but a MH does. I am told the glass will diminish the ray almost completely?

Also some other growers i know will take the glass off for the last week to 10 days.

I

How about it stoners :bigjoint:... anyone have any info they would like to share? I really like the hoods and they have produced great yields.
 
nomofatum

nomofatum

Well-Known Member
dbdweller said:
What i would like to know is not the basic about closer and heat but:

An Hps does not put out UV so the glass has no effect but a MH does. I am told the glass will diminish the ray almost completely?

Also some other growers i know will take the glass off for the last week to 10 days.

I

How about it stoners :bigjoint:... anyone have any info they would like to share? I really like the hoods and they have produced great yields.
Click to expand...
1. If the MH bulb doesn't give a UVB warning on the package or documentation somewhere, then it has a UVB filtering lining on the bulb. Some old time users were surprised when the UVB filters starting being used and their bud quality went down.

2. Glass reduces all light, but UVB light more than others, UVB also does not reflect off of a white surface.
3. Glass includes the glass of the bulb, if you go through more than 1 layer of glass you will lose too much of the UVB to really be very useful.
4. UVB sources: ATI True Actinic T5, T5/T8 10% UVB Reptile bulbs, CFL10% UVB reptile bulbs, 10% UVB Tanning bulbs.

I would worry about UVB separately from your main lighting, then you can run UVB with whatever other combo's you choose. If you can fit some T5 or T8 lights next to your HID I would, you can put UVB bulbs plus other supplemental bulbs in those fixtures. Then you can run a dash of the opposite of your main light. A bit of reds 3500k with your MH in veg, a bit of 6500k with your HPS in flower, and a bit of UVB also in flower.
 
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nomofatum

nomofatum

Well-Known Member
If heat is an issue the cooled hood will help, if heat is not an issue the extra light will help. If you run all year and have heat issues part time you can either remove the glass or switch reflectors for the season.

The UVB tanning bulbs I use put out about 3.5x the UVA as it does UVB with the rest being visible spectrum mostly in the neighboring blues. From what I have seed the other UVB bulbs are similar, check spectrum charts of specific bulbs you choose if available.
 
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bellcore

bellcore

Well-Known Member
Hey Nomo, what would your choices be? Maybe I should keep one of the 6500k bulbs in there for a more diverse spectrum?

I just picked up a used Sun Blaze T5HO-24 on craigslist yesterday to supplement the 250w HID. It has 4 6500k veg bulbs in it.

For flower I'm thinking
(2) 3000k generic bulbs
(1) ATI True Antic (approximately 420nm) or (1) ZoomMed Reptisun 10 UVB
(1) ATI Coral Plus (around 15000K+) or (1) ZooMed OceanSun 10000k 420 Daylight
 
nomofatum

nomofatum

Well-Known Member
bellcore said:
Hey Nomo, what would your choices be? Maybe I should keep one of the 6500k bulbs in there for a more diverse spectrum?

I just picked up a used Sun Blaze T5HO-24 on craigslist yesterday to supplement the 250w HID. It has 4 6500k veg bulbs in it.

For flower I'm thinking
(2) 3000k generic bulbs
(1) ATI True Antic (approximately 420nm) or (1) ZoomMed Reptisun 10 UVB
(1) ATI Coral Plus (around 15000K+) or (1) ZooMed OceanSun 10000k 420 Daylight
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Can you find any spectrum charts from ZooMed? I'm left guessing what they actually put out.

I can't decide if I would prefer 1 of each or keeping the 2 3000k as you said. Normally I wouldn't use 3000k in supplemental during flower since the main light would be putting out the same colors, but your supplemental is too big compared to your HID to be treated as purely supplemental.

Go with ATI if you can't find a chart for the ZooMed ones.

The HID will be HPS in flower right?
 
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Diabolical666

Diabolical666

Well-Known Member
The MH bulb contains mercury. Having the glass on the hood is a good idea incase the bulb fails and explodes. Having mercury everywhere would be dangerous. UV dissipates in cheap HPS bulbs within 6 mths
 
dbdweller

dbdweller

Active Member
nomofatum said:
1. If the MH bulb doesn't give a UVB warning on the package or documentation somewhere, then it has a UVB filtering lining on the bulb. Some old time users were surprised when the UVB filters starting being used and their bud quality went down.

2. Glass reduces all light, but UVB light more than others, UVB also does not reflect off of a white surface.
3. Glass includes the glass of the bulb, if you go through more than 1 layer of glass you will lose too much of the UVB to really be very useful.
4. UVB sources: ATI True Actinic T5, T5/T8 10% UVB Reptile bulbs, CFL10% UVB reptile bulbs, 10% UVB Tanning bulbs.

I would worry about UVB separately from your main lighting, then you can run UVB with whatever other combo's you choose. If you can fit some T5 or T8 lights next to your HID I would, you can put UVB bulbs plus other supplemental bulbs in those fixtures. Then you can run a dash of the opposite of your main light. A bit of reds 3500k with your MH in veg, a bit of 6500k with your HPS in flower, and a bit of UVB also in flower.
Click to expand...
So all the bulbs now have the filter that do not say it? I use both through out the cycles. MH and HPS. Started going to these hoods because i got a great deal but now i am having to redesign it looks like. So do you think just taking the glass off from the start of waiting till the last couple weeks would help?

I should have bought the Plasma lighting when it was low enough then.
 
dbdweller

dbdweller

Active Member
blimey said:
I'm not too into optimizing light spectrums and shit but my bestfriend is, and I hear about it. Alot. I know he thinks the glass fucks up the spectrum. He recently told me this was the best light on the market, http://hydrobuilder.com/solis-tek-1000-watt-double-ended-ballast-bulb-and-reflector-combo.html with the 10k bulb. Basically a double ended mh bulb with an open reflector.
Click to expand...
Yes i am hearing bad things about them now
Blimey have you heard about plasma lights? Expensive as hell but will give you a grow like you have never had before. Light spectrum is the same through out the grow. ends and middle.
 
Gquebed

Gquebed

Well-Known Member
I did a cool tube grow and a bare bulb grow back to back with the same strain and all other conditions the same and i couldnt tell any difference, except i could get the cool tubes down closer on the plant...so 6 of one and half-dozen of the other??? I dunno...
 
dbkick

dbkick

Well-Known Member
dbdweller said:
Yes i am hearing bad things about them now
Blimey have you heard about plasma lights? Expensive as hell but will give you a grow like you have never had before. Light spectrum is the same through out the grow. ends and middle.
Click to expand...
Gavita recommends using the plasma as supplemental light and in combination with an 1kw hps.
Not enough reds in plasma and the ones that do hit in the red spectrum you're changing out the emitter a lot if you want to keep the reds..
 
dbdweller

dbdweller

Active Member
Really had not heard that. I will have to research more on that thanks

changing it a lot. more then 2 cycles? The pictures i have seen and the one friend who bought it a long time ago when you could get 1200. i guess 300 is the max now a days.
 
nomofatum

nomofatum

Well-Known Member
dbdweller said:
So all the bulbs now have the filter that do not say it? I use both through out the cycles. MH and HPS. Started going to these hoods because i got a great deal but now i am having to redesign it looks like. So do you think just taking the glass off from the start of waiting till the last couple weeks would help?

I should have bought the Plasma lighting when it was low enough then.
Click to expand...
My understanding is that this happened quite a few years ago, like the 90's. The filter coating was added to help with UVB issues leading to lawsuits and medical issues. No point in putting out harmful UVB light in a warehouse, parking lot, or for the security light on the barn... Really old bulbs or some bulbs for growing may not have the filter.
 
daybreaker

daybreaker

Well-Known Member
Good lord,and I thought back in the day it was my glassless vertical bulb round reflector that made my bud so good.
 
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