It might be interesting to see the heat energy absorbed on a flat black surface with MH vs HPS of same wattage (measure the temp). Wouldn't a blue photon have more heat energy than a red photon?
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MH vs HPS in bloom
- Thread starter the gnome
- Start date
I think you need to take into consideration how the receiving object deals with that energy: will it be used in its chemical processes or is it dissipated in heat? In my experience the plant is warmer under MH, whether that is by irradiated IR or energy dissipation I can't tell. Though I believe that in a plant indeed more heat is dissipated with blue photons. In general a lot of heat is dissipated when the saturation level of the plant is reached.
NotSoNewbie
New member
I have a two way ballasts and both types of bulbs
Would it be considered stressful to switch out the hps for the mh bulb for a day every once in while in bloom? Maybe 1 day a week MH and the rest HPS
Anyone tried?
Would it be considered stressful to switch out the hps for the mh bulb for a day every once in while in bloom? Maybe 1 day a week MH and the rest HPS
Anyone tried?
Perfect spectrum.I personally use one hortilux super hps to each hortilux super blue dual arc.im thinkin a whole grow in those super blues..best bulb ive used yet imo.what kinda bulbs do you run GS?
hmmm... my 2 cents, for what it is worth
Plants have developed millions of years under sunlight. They are optimally adapted to that specific spectrum. That is something that pops up in every research paper about optimal spectrum for plant growth. Some plants thrive under (extra) red (and fortunately cannabis does so too!) but generally they need it all. Forget McCree when you are working with high intensity lighting, his curve is applicable for 100 umol s-1 m-2. At higher intensity the color green is even more more efficient than blue and red. Also UVA and B are "trending topics'.
Now MH lamps have, without a doubt, a better spectrum for plant growth than HPS. Problem is that they are not as efficient as HPS, though the new medium power CDMs come closer.
I have seen MH versus HPS grows and have done MH versus HPS grows, even CDM versus HPS. My experience is that MH is hotter than HPS. The yield of comparable MH lamps is lower than HPS, though some came very close.
So the MH do much less micromols but have a better spectrum. I think that is how you get a good yield per micromol. HPS spectrum is much worse, and particularly for the photosynthetic system, that needs blue light for maintaining itself. So though you get much more micromols to your plant, the yield per micromol is a bit less.
imho the old-school method of mixing MH 400 and HPS 600 works still very well if you choose for a traditional HID solution. You have the advantage of both that way. That's how a greenhouse works, but with sunlight.
I would stay away from 2-in-one lamp constructions for two reasons:
1. Lower wattage lamps are always less efficient
2. You have to toss the complete lamp after 6 months as the MH does not last very long, while the HPS may not even be half way.
In a small room they are hard to mix though, but that is a given.
A last thing you need to remember: Blue photons have more energy than red photons, (up to 1.7 times) and take more energy to create. So a blue lamp usually is less efficient in generating photons than a red lamp.
What setup would you recommend then?
(1) 400w MH + (1) 600w HPS ?
How does the LEP compare to a 400w MH (off topic a bit)
TR
I agree with passing on a dual spec bulb but for other reasons.
with a dual spec bulb you have a 600W HPS and a 400W MH in a bulb
but you have to keep that at 1000W distance,
(due to 1000W heat)
your at a disadvantage right there using 400/600 at 1000w distance.
even with air cooled equipment, you can get closer but its still the same premise
of using a lower wattage bulb further away.
if you want Mh and hps get two separate bulbs of matched wattage
I have read a few times on and since og that some growers use hps for the majority of flowering(for weight?) and mh for the last few weeks(for resin and finishing?). I don't see what the benefits of doing the opposite would be.
NSN I wouldn't do that sounds like too much work and could possibly stress the plants.
NSN I wouldn't do that sounds like too much work and could possibly stress the plants.
HPS/MH lamp efficiency generally deteriorates when you have lower power lamps. Matching wattage will not result in light balance: MH is less efficient than HPS. I think 400W MH is more than enough to match 600W HPS. It's less than half the ppf of HPS, but you don't need more than about 10% blue spectrum as a minimum.
High lamps and overlapping throws is the answer, ot keep the lamps close together if you only have 2. I used to do it in cooltubes, then I had to use a total of 1000W in a 1.2x1.2 tent. This is 5 years ago, Amnesia Haze in scrog and a few Warlocks from Gerrit.
Pretty damn tasty
High lamps and overlapping throws is the answer, ot keep the lamps close together if you only have 2. I used to do it in cooltubes, then I had to use a total of 1000W in a 1.2x1.2 tent. This is 5 years ago, Amnesia Haze in scrog and a few Warlocks from Gerrit.
Pretty damn tasty
I am sorry i didnt take pics, my camera is gone. Lost it powder skiing. HPS is the winner again. it beat the mh in yield, frostiness, and over all quality.
use both if possible but if you have to chose go with the higher wattage even though it is mh.
well first make sure the ballast can run both bulbs. many cant. then if the 400w can take hps, go hps with the 400 watt. I like the hortilux eye bulbs. giving me great results right now.
c'mon now....
your living up to your ic nickname
I never ever said to read only the 1st page
people just seem to read that last 2-3 pages of this thread when they take a look
a few more of the latest in the bloom room using all MH in veg and bloom.
trimmed a bunch of larf for hash in the last few days and its frosty-n-Xtremely sticky
now this needs to be said again every 5 pages or so....
it gets lost in the mix
it is **strain dependent/gentetics** how a plant perform under hps or mh
some don't do well under hps some excell and the same goes for Mh
MY CSG secret recipe did well under hps,
i had no complaints until..... i used Mh in bloom on it
same plant under mh produced way more weight,
40% more!!
nugz were way tighter and denser than the hps secret recipie side of it
here is mypost.... #97
currently@42 daysok... thee final tally in
total take, both sides combined is............................ ..................... 162g
HPS side is 61.3
AND
Mh side is----drum roll plzz------------------------------------------------------------------------------------> 101.6
multi strain,
BOG bogglegum
CSG secret recipe
GGG, leia og
REZ KQK
and GH blockhead
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I'm in the middle of harvest and just realized something about my Block Head strain.
in seed and 1st clone run the yield was poor, but very frosty and a keeper but for the weight issue. i ran it again last run to give it one more try, but i let my clones go already.
this last run the cola's were nothing like the 1st 2 runs?
nite and day difference and ive been beating my brains why this last round i'm getting arm length, beer bottle girthed cola's??
the seed run was hps in bloom, the 1st clone run was under 1 MH and 1 hps and the BH was under the HPS side of the grow pretty far from the Mh side.
my 3rd run with it, this one right now and i ran all Mh .
this is the only difference from the 1st 2 runs
;
these are from the all MH run,
same strain
same pheno
here is the cloned pheno from the hps mh grow in last run,
this is the top of the plant
this pheno under hps there was less leaf as the Mh one above but after the
trim yesterday they still beat the HPS bud in size by quite a bit
in seed and 1st clone run the yield was poor, but very frosty and a keeper but for the weight issue. i ran it again last run to give it one more try, but i let my clones go already.
this last run the cola's were nothing like the 1st 2 runs?
nite and day difference and ive been beating my brains why this last round i'm getting arm length, beer bottle girthed cola's??
the seed run was hps in bloom, the 1st clone run was under 1 MH and 1 hps and the BH was under the HPS side of the grow pretty far from the Mh side.
my 3rd run with it, this one right now and i ran all Mh .
this is the only difference from the 1st 2 runs
;
these are from the all MH run,
same strain
same pheno
here is the cloned pheno from the hps mh grow in last run,
this is the top of the plant
this pheno under hps there was less leaf as the Mh one above but after the
trim yesterday they still beat the HPS bud in size by quite a bit
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coloradcannabis
Member
Honestly I am a fan of MH/HPS flowering but I just got a 1000 HPS and will be using it veg to bloom. From my experience and research nothing really beats intense HPS light for big potent buds.
