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MH Lighting For Entire Grow?

Longhair

Member
Hello,
How Many People Use Only MH Lighting For The complete Grow. Germ To Harvest.
I've Read Allot About HPS For Complete Grows, But Nothing About MH's.
Thank You
 
that is how i started indoors 12 years ago. the biggest difference is in lumens(light available for plant growth). average mh put off about 115000 lumens and hps 140000, for the same amount of electricity. i never used mh again after i found this out. over 4 hps equal 5 mh in a room if looking at lumen output. 8 eqauls 10 etc... use hps for grow and bloom, and stop paying shady old grow store owners twice what you should with blue/red spectrum. i look at it as purely market base profitering. if a light it brighter, the plant grows more, pretty basic. if you wanna go with mh do it, cuz they work awesome, but when you pay your bill for less light it is a burn in my books:)
 

mean mr.mustard

I Pass Satellites
Veteran
The blue light found in the MH is totally lacking in the HPS. Vegging plants use blue light to build chloroplasts, the powerhouse of the plant... you may lose a lil on the lumens but the quality of light is better for the plant. In budding HPS's cause a more dense bud but I've found that although MH grown bud is a little fluffier it seems to get me higher than its twin harvested from under an HPS... I'd go for it if I were you.
 

azpeen

New member
I've tried both. Metal Halides are much better for vegetation than Sodium lamps. Like mean.mr.mustard said, vegging plants use primarily blue light, so getting a few more lumens out of a lamp isn't the whole picture. The plants benefit from more light in the spectrum of light that is needed by the plants. If you need to go with one lamp, probably depends on the situation. If it's a short grow-space limiting plant height, I'd go with a good enhanced spectrum halide. If height isn't a problem, then a Sodium will probably give higher yields. Both seems to work well to. (2) Halides for pure veg, (1) Halide / (1) Sodium for transition, (2) Sodiums for Flower. Dual arc bulbs are nice, too, but I'd opt for two separate lamps for lower long term replacement cost.
 

FunkBomb

Power Armor rules
Veteran
I run the MH during veg and the HPS in flower. I have been eying some of those 3000 kelvin red MH's that some companies make. I doubt it would be able to produce what a 2100k HPS can do though.

-Funk
 
hortilux super hps have blue and violet in them more so the standard hps, and more lumens. potency is genetic, not dictated by light spectrum. spend twice the money if you want, the world is what you make it. i have yet to see any scientific data proving any blue/red plant needs. if people from this post discussing them can please provide the i would much appreciate it for my library:) the only study i have seen is that uvb potentially increases resin content in anuual, resin producing dichotemous plants.
 

mean mr.mustard

I Pass Satellites
Veteran
I like this thread :)

I'm actually impressed to see it! This reminds me of the old days here :joint:

azpeen-- I like your schedule... makes sense to me

FunkBomb-- I just saw an ad in a mag last week and thought the same thing... have you seen the uv ones??

medicine man bc-- I must say that potency is mostly genetic and totally dictated by light spectrum...
 

mean mr.mustard

I Pass Satellites
Veteran
PAR and Plant Response Curve

Just as humans need a balanced diet, plants need balanced, full-spectrum light for good health and optimum growth. The quality of light is as important as quantity. Plants are sensitive to a similar portion of the spectrum as is the human eye. This portion of the light spectrum is referred to as photosynthetically active radiation or PAR, namely about 400 to 700 nanometers in wavelength. Nevertheless, plant response within this region is very different from that of humans.

The human eye has a peak sensitivity in the yellow-green region, around 550 nanometers. This is the "optic yellow" color used for highly visible signs and objects. Plants, on the other hand, respond more effectively to red light and to blue light, the peak being in the red region at around 630 nanometers. The graphs below show the human eye response curve and the plant response curve. Note the vast difference in the contours.





In the same way fat provides the most efficient calories for humans, red light provides the most efficient food for plants. However, a plant illuminated only with red or orange light will fail to develop sufficient bulk. Leafy growth (vegetative growth) and bulk also require blue light. Many other complex processes are triggered by light required from different regions of the spectrum. The correct portion of the spectrum varies from species to species. However, the quantity of light needed for plant growth and health can be measured, assuming that all portions of the spectrum are adequately covered. Light for plants cannot, however, be measured with the same standards used to measure light for humans. Some basic definitions and distinctions follow that are useful in determining appropriate ways to measure the quantity of light for hydroponic plant growth.

... yadda yadda ya...

c/o sunmasterblahblah.com

yeah there are graphs... go find em :D
 

geopolitical

Vladimir Demikhov Fanboy
Veteran
I currently have one box that's strait MH all the way through. Works well. Doesn't yield quite as well per watt as the HPS, but it does very well all the same.
 
listen to growers, not store owners. it took a while but even ed rosenthal admitted the "the best overall bulbs" were hps, specifically 600w. great info all, n good luck
 

mean mr.mustard

I Pass Satellites
Veteran
600W HPS is the most efficient HID bulb (LPS is really the most efficient but the spectrum sux)
... if lumens per watt floats your boat :)
 

azpeen

New member
hortilux super hps have blue and violet in them more so the standard hps
These are the only HPS lamps that I use, now.
listen to growers, not store owners.
Amen to that. Some store owners still tell me to mix up nutrients per the instructions.... right??!! LOL.
azpeen-- I like your schedule... makes sense to me
This is what I've settled on from several years experience. It's probably more expensive than what someone just starting would want to spend. If you already have reflectors and ballasts, the only cost is electricity & lamp (bulb) replacement. The lamps end up lasting twice as long or more if there being switched in a planned manner. One catch is that the dual lamp reflector that I use tends to project one lamp (bulb) one direction and the other in the opposite direction. This isn't as big an issue on the light track.
i have yet to see any scientific data proving any blue/red plant needs.
Interesting point. I never really required a study for proof on this one. The results speak for themselves.

I actually experimented on the last couple of grows (really cuz the life was up on my Metal Halides). Both grows were started with 1000W lamps, one with the Hortilux Super HPS and the other with Son Agro Metal Halide (Red type I think, I'm not there). Both grows were the same strain (G13 Labs Purple Lady). Within the first 3 weeks, the HPS vegged plants were 2 feet tall with large node spacing. The finished out close to 3-4' (way taller than I like). The end results were still good, but height was approaching the limits of the space.

The Metal Halide plants, which were started initially under the Hortilux "Blue" 400W, then transferred to the 1000W Son Agro. At 3 weeks, they were about 14" tall and finished (finishing this week) out at about 24" tall. I may be forgetting some mundane height affecting detail here, but this type of result has been proven by experience time and time again. Wish I had some studies to verify the results.
 

azpeen

New member
These are the only HPS lamps that I use, now.

Amen to that. Some store owners still tell me to mix up nutrients per the instructions.... right??!! LOL.

This is what I've settled on from several years experience. It's probably more expensive than what someone just starting would want to spend. If you already have reflectors and ballasts, the only cost is electricity & lamp (bulb) replacement. The lamps end up lasting twice as long or more if there being switched in a planned manner. One little catch is that the dual lamp reflector that I use tends to project one lamp (bulb) one direction and the other in the opposite direction. This isn't as big an issue on the light track.
i have yet to see any scientific data proving any blue/red plant needs.
Interesting point. I never really required a study for proof on this one. The results speak for themselves.

I actually experimented on the last couple of grows (really cuz the life was up on my Metal Halides). Both grows were started with 1000W lamps, one with the Hortilux Super HPS and the other with Son Agro Metal Halide (Red type I think, I'm not there). Both grows were the same strain (G13 Labs Purple Lady). Within the first 3 weeks, the HPS vegged plants were 2 feet tall with large node spacing. The finished out close to 3-4' (way taller than I like). The end results were still good, but height was approaching the limits of the space.

The Metal Halide plants, which were started initially under the Hortilux "Blue" 400W, then transferred to the 1000W Son Agro. At 3 weeks, they were about 14" tall and finished (finishing this week) out at about 24" tall. I may be forgetting some mundane height affecting detail here, but this type of result has been proven by experience time and time again. Wish I had some studies to verify the results.
 

wick.96

Member
MH = old school bulbs, HPS = new school, hortilux newer school. CMH = even newer school.

That being said a good friend of mine asked me the same question the other day.

Ideally 1k watt HPS and a 1k watt MH mixed will give you the best results (maximum lumens/maximum spectrum). Or alot of growers use purely hortilux bulbs (a specialty HPS bulb) in the 600Watt or 1000Watt HPS variety.

MH alone in flowering is not a contender anymore simply put, there are more efficient bulbs out there.

CMH or ceramic metal halide (a specialty MH bulb), offers spectrum enhancements as well, red/orange. Is the newest bulb however only offers this particular enhanced spectrum at a reduced lumen output. The biggest bulb offered is 400watt.
 

mean mr.mustard

I Pass Satellites
Veteran
MH = veg, HPS = flower

Seems simple enough yet satisfies all of the previous parameters

Efficiency isn't necessarily the goal of some growers... some people don't even see $$ when they gaze into their garden :yoinks: :eek: :yoinks:
 

*mistress*

Member
Veteran
sunmaster warm deluxe is excellent metal halide bulb - for entire grow. will develop nodes tightly together. final fruit denser w/ mh (good mh w/ red). neutral deluxe has similar spectral output for less pieces of silver. both can readily match hps for final quality of fruit.

best is mix of mh+hps+uvb though.

a bit leafier, maybe, but solid tomatoes. would select sm warm over eye hortilux; but only for final fruit texture.

this may be helpful:
https://www.icmag.com/ic/showthread.php?t=108993
lighting conversion data

enjoy your garden!
 
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