Ceramic Metal Halide (CMH)

[Illumination]

I am done with all forms of HID, including CMH. I think LEDs are mature enough to consider for a serious grow so am going to try and go that route. I'll put up build threads and journals and whatnot when I get started.

I just wanted to wave bye to all the CMH growers.

Have fun wasting your money and if you need to waste more I have this superbloom food that is exactly what the plants need to make mediocre yields and waste your time as well for $300 a litre...should fit right in with the rest of your plan...jk
Have fun and good luck

 

[onegreenday]

I was thinking today that I'd replace my 1k horty with3
400 watt cmh. Yes 3 small umbrellas in a row.

so 36" wide by 9-11 feet long area of coverage

and get lots of blending of the bulbs.

I want to make my own parabolics out of dimpled aluminum

90% reflective soon.......be better than white I think.

Okay, guys... I need your opinions. Right now I'm using 1 400w cmh for veg and 1 separate 400 watt cmh for flowering. I'm 5 weeks through flowering so far and like what I see so far for the most part, but I grew the plants a little too much in veg, and so they ended up pretty large after stretching the first 3 weeks of flowering... and the cmh doesn't penetrate well enough to really get to the middle-to-bottom areas of the plants.

So, I'm planning ahead for the next run now. I'm going to keep using a 400 watt cmh for veg. I think they work great for veg and are big enough to grow out some nice mothers... but what do you guys think I should do for flowering?

2 x 400 watt CMH SOG style so the plants stay small and light penetrates to the bottom OR a single 1000 watt HPS hung vertically with plants trained around it in a circle?

I think vertical style growing is the most efficient from what I've seen, but unfortunately I don't think CMH light penetrates well enough to be used well vertically... and although I like what I've seen of the CMH so far in flowering, I have a strong feeling that 1000 hps would provide significantly bigger yields due to light intensity and penetration, especially in a veritcal setup.... I haven't yet made up my mind though. 2 400watt CMH kept really close to a bunch of smaller plants would probably do quite well.

Does anybody have any pictures of harvests from 2 or more 400 watt cmh? What's the most you guys have been able to pull from a setup like that? If anybody has done any tests with multi CMH vs 1000 watt, could you share your results and opinions?

 

[Illumination]

HID bulbs do NOT emit UV. That is a period at the end of the sentence.

I guess this should be posted on every single page as some keep trying to promote the myth that UV can be gotten from an HID bulb.

What is so hard? if perchance some company sold an HID bulb with detectable UV the feds would show up at their door with a writ and the factory would make no more. If there is a non-american company making HID's with UV they certainly are not going to piss off the USA by illegally selling it on the black market, not enough profit margin.

Thank you for your time.

Wow thankl you ...so now I am going to send back my extech uvb meter and tell them it is malfunctioning detecting a rather decent (about 1/2 of "optimum" if there is such a thing actually known as of yet)amount of uvb at 18 inches away from the bulb...So glad I will link your authoritative post as proof that their instrument is faulty and demand a new one

 

[VolcanoVapin]

I was thinking today that I'd replace my 1k horty with3
400 watt cmh. Yes 3 small umbrellas in a row.

so 36" wide by 9-11 feet long area of coverage

and get lots of blending of the bulbs.

I want to make my own parabolics out of dimpled aluminum

90% reflective soon.......be better than white I think.

I was kinda hoping for people who already made tests like these, not just planning to...

Anyways, I wouldn't get rid of that 1000 watter until after you try out what you're talking about. The plants need to stay very small for the 400w cmh to cover a 3x3 area... Mine really are only covering maybe a 2x2.5 area and the plants on the edges aren't getting that much light... they also only penetrate about 12-16" inches past the canopy with any intensity. This is why I'm considering selling off one of my 400watt cmh and replacing it with a 1000 thousand watt hps for flowering... I do want to use the HPS in a vertical setup to really get the max out of it too though.

Over the last few months of using the CMH, I think they are best suited to veg and SOG grows with SMALL plants and the light as close as possible to the tops of them... I'm really starting to think I'd be better off with a larger watt HPS for flowering. I'd love to see some pics proving me wrong though...

 

[onegreenday]

under 1k horty w 45" parabolic vertical I cover 7-11 plants
with the small parabolic I cover 4 small plants with cmh (I ran before), so 12 total for 1200 watts. with the blending from 3 light sources.........

I was kinda hoping for people who already made tests like these, not just planning to...

Anyways, I wouldn't get rid of that 1000 watter until after you try out what you're talking about. The plants need to stay very small for the 400w cmh to cover a 3x3 area... Mine really are only covering maybe a 2x2.5 area and the plants on the edges aren't getting that much light... they also only penetrate about 12-16" inches past the canopy with any intensity. This is why I'm considering selling off one of my 400watt cmh and replacing it with a 1000 thousand watt hps for flowering... I do want to use the HPS in a vertical setup to really get the max out of it too though.

Over the last few months of using the CMH, I think they are best suited to veg and SOG grows with SMALL plants and the light as close as possible to the tops of them... I'm really starting to think I'd be better off with a larger watt HPS for flowering. I'd love to see some pics proving me wrong though...

 

[khoi_sook_ya]

Hi Everyone

Great forum and great info.

I am a long time grower, and in the last 20 years, there have been some good products to improve our hobby and some snake oil (LEDs and Phototrons).

So imagine how happy I was to find this thread explaining the new "funny looking MH lamp I bought today" for my new aero micro grow. It is enclosed in glass, runs very cool, as I made them turn it on a few times, and is def not mercury vapor. More like an HPS.

This was in a China market, as I live overseas, and could not discuss too many details as they didn't speak the native language very well either. It is of course China made.

My question is this. Everyone from the very 1st postings are talking mainly of Philips bulbs. Any chance my bulb is a Chinese copy, emiting the same spectrum? Likely? It is def not Philips or any other name brand.

Do I need to change the bulb?

And how many Blondes will I need to change said bulb?

Thx guys. Great community. Great growers.

 

[onegreenday]

there's usually a number on the bulb.

google it & if it's chinese u can translate the page
and find out what you have.

Hi Everyone

Great forum and great info.

I am a long time grower, and in the last 20 years, there have been some good products to improve our hobby and some snake oil (LEDs and Phototrons).

So imagine how happy I was to find this thread explaining the new "funny looking MH lamp I bought today" for my new aero micro grow. It is enclosed in glass, runs very cool, as I made them turn it on a few times, and is def not mercury vapor. More like an HPS.

This was in a China market, as I live overseas, and could not discuss too many details as they didn't speak the native language very well either. It is of course China made.

My question is this. Everyone from the very 1st postings are talking mainly of Philips bulbs. Any chance my bulb is a Chinese copy, emiting the same spectrum? Likely? It is def not Philips or any other name brand.

Do I need to change the bulb?

And how many Blondes will I need to change said bulb?

Thx guys. Great community. Great growers.

 

[stonedar]

another clue would be what type of ballast it is run on. if it's magnetic 400w HPS ballast only then it could be a knockoff CMH

 

[Anti]

The reason everybody is so hyped up about the phillips bulb is that they're the only known OPEN-FIXTURE RATED CMH bulb on the market. It has an extra glass tube to help prevent explosive burn-out.

None of the others (to my knowledge) are open-fixture rated. That is the reason to go Philips retro-white.

(Especially if you're like me and you are planning to run vert with no reflector.)

 

[khoi_sook_ya]

Thanks for the warm and helpful replies, guys ( or girls).

I do understand now.

And Vol Vapin, I would advise that heat is going to be a major factor in your endeavor to change over to a 1000HPS.

Regardless of how you hang it, ventilation and cooling MUST be improved over your current set up. The 1K is throwing alot of heat compared to what you are running now.

That should be your biggest concern.

 

[master shake]

Hello everyone, sorry if this is a redundant post... I haven't been able to keep up with this huge thread over the years.

Is anyone aware of or done or seen a side-by-side grow of hps vs cmh through flowering? Same grower, same cutting, nutes, same time different rooms?

I have had my cmh for 3 grows now but I can only let myself use it up to week 2-3 flower. I tend to see leafier plants by those who use the cmh all the way, but not always.

 

[Imhotep]

I did a temp check and my box is running too hot - it's a 63x47x130cm space that runs at about 32C / 89F with a 250 watt HPS, about 5-8 degrees C above room temperature. I've got a 75cfm fan, which I'll probably upgrade, but since both intake and exhaust are in the same room, heat tends to build up over the day.

In short, I'm wondering if a CMH would lower the overall temperature of my grow by a significant amount?

There's a few different takes on CMH temps in this thread, but the major consensus seems to be that it runs a little cooler but mostly just pushes the heat up rather than pumping it down towards the plants. If this is the case, i'm not sure if this would help my situation as the room my cab is in would still reach similar temps.

Thanks.

 

[onegreenday]

better to work on your venting.

my 400 CMH pumps out the heat...............

I did a temp check and my box is running too hot - it's a 63x47x130cm space that runs at about 32C / 89F with a 250 watt HPS, about 5-8 degrees C above room temperature. I've got a 75cfm fan, which I'll probably upgrade, but since both intake and exhaust are in the same room, heat tends to build up over the day.

In short, I'm wondering if a CMH would lower the overall temperature of my grow by a significant amount?

There's a few different takes on CMH temps in this thread, but the major consensus seems to be that it runs a little cooler but mostly just pushes the heat up rather than pumping it down towards the plants. If this is the case, i'm not sure if this would help my situation as the room my cab is in would still reach similar temps.

Thanks.

 

[khoi_sook_ya]

Well, hell...The ballast is a BHL250 L 200 HID.

Dunno what that means, as far as answering if I have a CMH or not...now I see it is the bulb I should be looking at.

Too hot now, but it looks like it says jlz 250 idx.

Whoa...I'm blinded now....gonna start my micro blog with pix.

Aero 4 site with 250MH in a cab. NYC Diesel & Bubbleberry.

Peas.

 

[White Lady]

Hi,
Complete phase one of the better light bulb? GE 3000K or 4000K Philips Retro White?
Thank you.....

 

[master shake]

Hi,
Complete phase one of the better light bulb? GE 3000K or 4000K Philips Retro White?
Thank you.....

Not sure what you're asking, but for overall growth I'd go with the 4000k retro white.

 

[messn'n'gommin']

Hello everyone, sorry if this is a redundant post... I haven't been able to keep up with this huge thread over the years.

Is anyone aware of or done or seen a side-by-side grow of hps vs cmh through flowering? Same grower, same cutting, nutes, same time different rooms?

I have had my cmh for 3 grows now but I can only let myself use it up to week 2-3 flower. I tend to see leafier plants by those who use the cmh all the way, but not always.

I've seen where a few have said as much. But, never followed up on it. As far as I can tell, there is a reduced yield, so, it's not the first choice for commercial growers. However, counter that with better quality weed and the convenience of one light, one ballast and no switches and you have a great lamp for a personal use grower. Even then, there are a few who use the 400w CMH as supplemental lighting for 600w and 1000w HPS lamps.

All that aside, watt for watt, I think it's the best HID veg bulb out there!

As far as too many leaves, yeah, I've noticed that too! But, I never saw any real explanation of why too many leaves was necessarily a bad thing. I suppose a small pair of sharp scissors would come in handy, though.

hth

 

[Phaeton]

Where a leaf appears, a branch or bud is starting also at the base of the leaf stem. Under veg these are all branches and the leaf can be cut as soon as the branch is firmly established. Under 12/12 it starts being mostly buds starting at the base, these leaves get left on to feed the bud. This is my rational for cutting a few leaves every single day, feels useful.

This comes up as I use CMH/HPS just to get that extra without slowing bud growth.

4000K Phillip's, the GE seemed slightly pinkish to my eye. :kitty:

PS: my UVB is from reptile bulbs, real world output of UVB from OSHA rated bulbs is ignored by my plants, totally.

 

[Greenheart]

"GS Yuasa currently offers a series of Eco-Cera products for different applications, ranging from 34w to 680w products."

from this June 1rst 2011 article. http://www.gs-yuasa.com/us/attention/pdf/20110601e.pdf

 

[taureauchien]

ok here's my question.
i'll start by saying i just got a 4 x 4 x 6 grow rent.
the heat issues are stupid, even with extra ventilation.
i started with a 600 hps in a hood with 275 cfm pushing the air out... temps held at 90 f.
i tried my 400 cmh next to my 600 hps under reflector wings with an air duct from my ceiling a/c vent directly into thetent plus a 13000 btu portable a/c with the exhaust vented out the tent,room,window.plus a 425cfm exhaust fan pushing out hot air... fukken thing was averaging 92-95 f.
now i have 8 300 watt equivilent cfl bulbs (home depot brand, 64 watts each) running instead with just the 425 and 275 cfm exhaust fans sucking out anything in the tent....hovering mid eighties for tent temp, but without nearly the same light output. but doing this until i get temps fixed.

now onto the question.
i thinking of doing a growzilla with 2 400watt cmh bulbs for 800 cmh watts coming out of one hood. will the glass insert hurt the output from these bulbs? especially in the uv dept.?

i will be getting a mack daddy exhaust fan to hook onto it, plus the other 2 exhaust fans sucking any and all heat out of that sucka. blown out the window. and keeping the ambient room temp as cool as affordable.
i know some people have said that mixing a cmh and a hps is the way to go. and some say a cmh is better by itself. either way 800 watts of anything in a 4 x 4 tent is strong.

but will heat be my issue? and how about light quality?
anybody use the growzilla with dual cmh bulbs?
how about one 4k bulb next to a 3k bulb?