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Ceramic Metal Halide (CMH)

messn'n'gommin'

ember
Veteran
Personally, I wouldn't think that there is all that much difference between the 3K bulb and a generic HPS bulb at 2700K. How one mixes and matches is largely a personal choice. I can see how adding extra RL to a CMH would go a long way to increasing yield while still taking advantage of the CMH's fuller spectrum.

But, all that aside, you may be better off solving your heat problem first. Mid-80's temps from 192w's of fluoro's in a 4x4 tent says volumes about a lack of airflow. The following link is as good a rundown on ventilation as any I have seen...anywhere!
“Ventilation 101,” by redgreenry
https://www.icmag.com/ic/showthread.php?t=112862

hth
 

taureauchien

New member
i read that and the negative pressure thing he was talking about is what i have going on.
some are saying they suck out the heat from a 600 watt hps with
a less than 300 cfm fan only. with maybe some oscilating fans circulating the 4x4 tent.
shit, i have double that in cfms and only cfls currently and still am to warm.
i'm even keeping the house at less than 65 degrees on the ac and still have 80's for tent temp.

i'm going to put back in a single cmh on a bat wing reflector with the fan blowing on it. if it is only going to above 80 anyways, i may as well use the proper light.

but if i get that growzilla and put either 2 cmh or 1 cmh 1 hps and a cfm output of over 700, will the glass lens cut the uv output or should i take that off.....if i take it off, i may as well just use my bat wings and 2 cmh
 

messn'n'gommin'

ember
Veteran
I think what they are talking about is venting the light on a closed loop system. On a closed loop system the tent still has its own separate ventilation system.

I may be way off base here, but you really need to address your heat problems first. Adding more wattage is only going to compound the problem. Could you describe your setup? It would go a long way towards solving the problem.

After that, you might want to consider adding CO2.
 

taureauchien

New member
sometimes things just dont make sense.
i removed 2 cfl's that were in a corner behind the oscilating fan.
added the cmh /batwing, moved the exhaust ducting up to the reflectr and temps read 77....all afternoon.
granted we were having a lot of rain today and the outside temps were cooler, but still, to have that big a drop after adding a cmh.
oh well, i aint complaining. neither are the plants i'm sure.
lets hope it isnt just because it rained all day
 

Anti

Sorcerer's Apprentice
Veteran
added the cmh /batwing, moved the exhaust ducting up to the reflectr and temps read 77....all afternoon.

My guess is that moving the exhaust is what gave you your current temp. CMH are said to "throw" less heat than other HID bulbs, which means that the majority of the heat coming off the CMH is rising UP. If you are exhausting directly above the bulb, most of the heat from the CMH is going straight out the exhaust.

If you still have oscillating fans in there, I'd recommend trying the following:

Put one fan directly under the bulb on the LOWEST setting. (You want to gently encourage a steady rising airflow (air rising toward exhaust) rather than powerful gusts of wind that will blow the heat around the cabinet.

(I learned this from the Vert section.)
 

Grow Tech

I've got a stalk of sinsemilla growing in my back
Veteran
Alrighty then....I won't even pretend I read all 277 pages. In fact, I've only skimmed a few pages now & then over the last couple of years. Hopefully what I've done to help others will keep me for getting flamed for asking newbie-ish questions....

I'm looking to expand my setup. I've been running a 600w hps cool tube and using PL-L floros to add some blue from veg through the first couple of weeks of flower. Im considering making my cool tube a dual lamp fixture using this assembly-
picture.php
I have some 400w HPS magnetic ballasts sitting around and I'm wondering if running a 400w CMH as the second lamp in my vertically hanging cool tube would be preferable to using 2 x 600w HPS for the veg period. After veg ( or within a couple weeks of going 12/12) I would probably go to 2x600w HPS.

My hope is that I could use less watts duringing the 18 hr/ day veg period, get better light spectrum for the veg phase & possibly have less heat generated which would be nice since I don't have a/c

I really like my PL-L floros and would be open to their continued use

Some more details...
As mentioned, the cool tube would be hung vertically. The girls would be trained onto wire trellises placed around the tube creating a circular wall of green with an aprx 2'-2 1/2' radius. I'd be growing in 4gal hempy buckets and probably try to keep the height down to 3-4' ( over the buckets). Its a 32" cool tube ( aluminum fittings on each end included

any input apprecitaed:tiphat:
 

Anti

Sorcerer's Apprentice
Veteran
I have some 400w HPS magnetic ballasts sitting around and I'm wondering if running a 400w CMH as the second lamp in my vertically hanging cool tube would be preferable to using 2 x 600w HPS for the veg period. After veg ( or within a couple weeks of going 12/12) I would probably go to 2x600w HPS. My hope is that I could use less watts duringing the 18 hr/ day veg period, get better light spectrum for the veg phase & possibly have less heat

Sounds like a good plan to me. Especially if you already have the ballasts sitting around.

Most of my homies in the vertical forum recommend NOT using cooltubes (which diminish the light hitting your plants) and using a fan, positioned directly beneath the lights, set to the lowest setting, to encourage a gently wafting upward moving column of air which will encourage the heat's natural tendency to rise. Couple this column of rising air with powerful extraction directly ABOVE the lights and extract the whole room 2x per minute for optimal results.

Here's an example of Maj. Cottonmouth's current setup:

picture.php


It sounds like he's doing almost exactly what you're talking about, except that he's using a 1000w HPS at the top and a 400w CMH at the bottom. Notice that there's no cooltube but there IS a fan directly below the column of light.

Hope this helps.
 

Pinball Wizard

The wand chooses the wizard
Veteran
Dual 400 CMH - 2x4 closet grows

Dual 400 CMH - 2x4 closet grows

I ready need to quit messing around...and get a third 400 light...:dance013:

I love a good (HD Diesel) 400 mag HPS ballast & CMH bulb....:tiphat:

...
 
F

Fastcast

What is the longest you've used your 400 w CMH for?I'm one the 10th month with the one I have.These bulbs work very well!
 

messn'n'gommin'

ember
Veteran
Most of them have about a 20K hour working life.

I have three 250's. Two that are about 3 years old with about 10k hours on them that I rotate with one about 2 years old and about 5K hours. The two older ones should be replaced, but I'm not losing sleep over it even with about 80% lumen maintenance. It's just a closet grow and I still grow more than I need with that.

hth
 
F

Fastcast

Most of them have about a 20K hour working life.

I have three 250's. Two that are about 3 years old with about 10k hours on them that I rotate with one about 2 years old and about 5K hours. The two older ones should be replaced, but I'm not losing sleep over it even with about 80% lumen maintenance. It's just a closet grow and I still grow more than I need with that.

hth
Hey messn,I remember reading numbers similar to that and really had a hard time with it when I figured the hours to years and was shocked,I never planed on using it that long.Either way I like hearing that you used yours for that long.The maintenance on this bulb is very impressive,at 80%,whats not to like about that?This run I'm using a conversion bulb along side it.Thanks for the reply.Safe groing
 

onegreenday

Active member
Veteran
It's best to incorporate light meters into a grow-op.

Only way to tell if bulbs are performing.

My old meter broke (after 12 yrs) now I can't tell

if my 1k hortilux is up to snuff; since it does not seem

as bright as the last one I used.

Measure a new bulb at a certain distance from the bulb
and mark the base with the foot candles.

Every 6 months run your meter check to see what your output is...



Most of them have about a 20K hour working life.

I have three 250's. Two that are about 3 years old with about 10k hours on them that I rotate with one about 2 years old and about 5K hours. The two older ones should be replaced, but I'm not losing sleep over it even with about 80% lumen maintenance. It's just a closet grow and I still grow more than I need with that.

hth
 
F

Fastcast

I really don't here about light meters to much,good idea but aren't they kinda pricy?
 
F

Fastcast

Thanks for the info onegreenday.This to me would be the best method,the light meter I mean.Safe groing
 

messn'n'gommin'

ember
Veteran
It's best to incorporate light meters into a grow-op.

Only way to tell if bulbs are performing.

My old meter broke (after 12 yrs) now I can't tell

if my 1k hortilux is up to snuff; since it does not seem

as bright as the last one I used.

Measure a new bulb at a certain distance from the bulb
and mark the base with the foot candles.

Every 6 months run your meter check to see what your output is...

Well said! A point to be made! An affordable tool for most! Maintenance and housekeeping is seldom given more than a passing thought and deserves more consideration! If nothing else than to clean bulbs, reflectors and intake prefilters...regularly!

Still,...lol...you're not going to find a lab in my closet. So, close guesses are good enough for my little garden.
 

onegreenday

Active member
Veteran
Fabian the old tech up at PL Light Systems told me he found quite a variance (25%) in output of different core & coil ballasts (all from the same manf.) when he did his testing.

The meter is good for checking the outputs between different lights also.

Hopefully the electronic ballasts perform better on their outputs,
than core & coil.

Well said! A point to be made! An affordable tool for most! Maintenance and housekeeping is seldom given more than a passing thought and deserves more consideration! If nothing else than to clean bulbs, reflectors and intake prefilters...regularly!

Still,...lol...you're not going to find a lab in my closet. So, close guesses are good enough for my little garden.
 

przcvctm

Well-known member
Veteran
Forgive me for asking something that I'm sure has been covered already, but this thread is so large that searching it is futile most of the time since a deletion here and there screws the whole thing up.

I have a SS#1 400w ballast that works great. Quiet, fires up 100% of the time and no flickering. But 400w is just a little too intense for my 5 sq.ft. cab. I ordered a Sola 250w online then cancelled it as soon as I read closer that the maximum ballast to lamp distance was only two feet.

I need 5-8' of cord. I also need simplicity and don't want to have to remote the ignitor to the hood or anything like that. My question; is there another brand that comes with a more powerful ignitor or would the Sola work with the ignitor it comes with?

Quality and performance a greater concern over cost.

edit> After several years of searching this thread in frustration ending with a vow of no more, I searched after posting this and found my answer. Sorry.
 

stonedar

Macro-aggressor
Veteran
Do you live in the US? this is a monster of a ballast, like the SS1 it's not for show it's for grow. quality parts, must weigh same as most 600w magnetic ballasts.
http://hydro-earth.com/grow-light-ballasts/7037-sg-250w-120240v-hps-ballast.html

distributed by hydrofarm SG ballasts have been around for a while, 5 year warranty UL listed
*be aware it does have a hydrofarm style cord connection not the standard/sunlight supply cord*
adapter is called a BAASR
http://hydro-earth.com/lighting-accessories/1340-receptacle-adapter-brand-s.html
 

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