MH vs HPS for yield?

[the gnome]

gnome, forget those light graphers, i trust ya. i mean 20 years is god damn long time to have experience, so you should know a thing or two.

could you recommend me the best mh bulb for my 1.2 x 1.2 x 2.0 meters tent? it must have 600w, or would it be better to make it 2 x 400w? i appreticate your help dude

although Ive been growing sincethe mid 70s Ive only been using lamps in the last 4yrs.
that quote on lite graphs and 20yrs exp. is from vapedg13
he's the one that uses the 4000K bulbs that i took my lead from when i started using MH in bloom and started seeing things that went against the "hps is the only bulb to use in bloom" i read and people reiterated.
and its not saying graphs are bunk,
but when people use them to say? debunk using MH in bloom and people that have had great success using them,
that's the point he's making imo


what tokersmoke said,
as long as it's a 4000K it''ll work for bloom

 

[flora420]

although Ive been growing sincethe mid 70s Ive only been using lamps in the last 4yrs.
that quote on lite graphs and 20yrs exp. is from vapedg13
he's the one that uses the 4000K bulbs that i took my lead from when i started using MH in bloom and started seeing things that went against the "hps is the only bulb to use in bloom" i read and people reiterated.
and its not saying graphs are bunk,
but when people use them to say? debunk using MH in bloom and people that have had great success using them,
that's the point he's making imo


what tokersmoke said,
as long as it's a 4000K it''ll work for bloom

alright cool, thanks dude. ive been watching some of your projects and i admire youre results, wish i could get nearly as good buds as you. specially liked your grow room project, sweet.

have you ever tried mixing hps and mh? if i ever choose to make it 2 x 400w, would 1hps and 1mh bulb be a good mix? or mh all the way?

 

[flora420]

sorry for dp, cant you edit your messages?

closest mh i found was 4200k, would that be the same?

 

[tokersmoke]

a quick answer is yes..But not the specific bulb he uses my mh is in the 5200k range and i love it.

 

[the gnome]

alright cool, thanks dude. ive been watching some of your projects and i admire youre results, wish i could get nearly as good buds as you. specially liked your grow room project, sweet.

have you ever tried mixing hps and mh? if i ever choose to make it 2 x 400w, would 1hps and 1mh bulb be a good mix? or mh all the way?

sure you can use both type of bulbs,
there's so many types of bulbs with all kinds of kelvin ratings out there you can get all kinds of results.
many peeps mix mh-hps and are happy with it.

I can only say for sure i get top shelf results using a specific bulb for bloom with my growing style... ymmv



you should read more about using specific bulbs
here's a thread i started a few years ago when i started experimenting with Mh in bloom
the 1st 15 pages have the best info imo,
then the more *hps is the only bulb to use in bloom" peeps start in.
https://www.icmag.com/ic/showthread.php?t=243060

 

[Jhhnn]

although Ive been growing sincethe mid 70s Ive only been using lamps in the last 4yrs.
that quote on lite graphs and 20yrs exp. is from vapedg13
he's the one that uses the 4000K bulbs that i took my lead from when i started using MH in bloom and started seeing things that went against the "hps is the only bulb to use in bloom" i read and people reiterated.
and its not saying graphs are bunk,
but when people use them to say? debunk using MH in bloom and people that have had great success using them,
that's the point he's making imo


what tokersmoke said,
as long as it's a 4000K it''ll work for bloom

I think you're mostly right, Gnome. I do think, however, that a spectral graph of the bulb you prefer would reveal a balanced output w/ various spikes, consistent with your results. I never could find that graph, but I'm sure it exists somewhere. Those spikes happily exist at the frequencies the plants need, even if that never was a design criteria. It really can be no other way.

I strongly suspect that some other MH bulbs may not be nearly as effective for growing, even if the light looks the same to us. I also suspect that the reason HPS bulbs work as well as they do is because they have just enough blue light for the plants to compensate for the lack in ways we don't really understand, either.

I'd love to be able to run a controlled experiment using some of the different lights available. Create 100 clones from a strain that's been dialed in, distribute the 4 dozen best into a dozen identical tent setups. Do that in one big room, feed them all from the same hydro reservoir, just with a different bulb in each tent. Tend them all, taking notes. Save & weigh the production from each tent- stems, fans, popcorn, sugar leaf & top buds. Have a panel of connoisseur testers evaluate each batch. Do it again, just to be sure that the results are repeatable. I strongly suspect that bulbs having more blue than standard HPS would produce better results.

As small growers, it's very difficult for us to eliminate all the variables to establish truly scientific results. OTOH, we can learn from each other, try different things as our circumstances allow. It's also hard to take chances when we have a method that works well, given that we all depend on harvests in one way or another.

I'm pretty much stuck with a horizontal bulb in a vent hood w/ two stage ventilation because of headroom, combined with the technical difficulty & expense of providing AC in our 6 plant grow. I really can't justify it. I intend to rework the whole thing late this summer with a little more room & better ventilation, at which point I *may* be able to add something like a 400w bare vert bulb or a Philips CMH.

Under more amenable circumstances, I'd be all over your bulb selection & methods like a monkey on a cupcake. Your girls are gorgeous.

 

[the gnome]

I think you're mostly right, Gnome. I do think, however, that a spectral graph of the bulb you prefer would reveal a balanced output w/ various spikes, consistent with your results. I never could find that graph, but I'm sure it exists somewhere. Those spikes happily exist at the frequencies the plants need, even if that never was a design criteria. It really can be no other way.
agreed jhnn


I strongly suspect that some other MH bulbs may not be nearly as effective for growing, even if the light looks the same to us. I also suspect that the reason HPS bulbs work as well as they do is because they have just enough blue light for the plants to compensate for the lack in ways we don't really understand, either.
oh yeah, Id have to say for sure, Ive treid the hi blu-K end of Mh bulbs and the buds were frosty, potent, but light and airy and horrible weight at harvest,
and I believe this is exactly where you hear Mh produces this and that if you use it for bloom,
and others are saying they are killing it using MH, iots the discrepency in the K rating of halides being used,
and as you say,
hps having enuff blu to make it happen in bloom
I'll add this... nearly all seeds available to us are from indoor strains that have been bred for decades blooming under hps,


I'd love to be able to run a controlled experiment using some of the different lights available. Create 100 clones from a strain that's been dialed in, distribute the 4 dozen best into a dozen identical tent setups. Do that in one big room, feed them all from the same hydro reservoir, just with a different bulb in each tent. Tend them all, taking notes. Save & weigh the production from each tent- stems, fans, popcorn, sugar leaf & top buds. Have a panel of connoisseur testers evaluate each batch. Do it again, just to be sure that the results are repeatable. I strongly suspect that bulbs having more blue than standard HPS would produce better results.
I'm amazed this hasn't been done yet! when i started my
MH VS HPS in bloom thread I was thinking as simple as this is to do, it really hasn't been addressed yet??


As small growers, it's very difficult for us to eliminate all the variables to establish truly scientific results. OTOH, we can learn from each other, try different things as our circumstances allow. It's also hard to take chances when we have a method that works well, given that we all depend on harvests in one way or another.
oh for sure jhnnn, when you have a killer harvest you don't want to change a single thing and risk not having that beautiful harvest, i nearly gave up on Mh in bloom because for 2 runs i used HI Kelvin blu bulbs, 6400K and 7200K,
it 2wasn't until I started my mh vs hps thread that vapeg13 started with his absolutely outstanding killer mh gro's using a ***4000K mh bulb***
after i got the 4000K mh bulb its been gravy since and my latest round in a sealed room has given me the largest buds Ive ever had in 4yrs

I'm pretty much stuck with a horizontal bulb in a vent hood w/ two stage ventilation because of headroom, combined with the technical difficulty & expense of providing AC in our 6 plant grow. I really can't justify it. I intend to rework the whole thing late this summer with a little more room & better ventilation, at which point I *may* be able to add something like a 400w bare vert bulb or a Philips CMH.

Under more amenable circumstances, I'd be all over your bulb selection & methods like a monkey on a cupcake. Your girls are gorgeous.

yup, sounds like you have a solid plan jhnn.......






.

 

[RB56]

I think you're mostly right, Gnome. I do think, however, that a spectral graph of the bulb you prefer would reveal a balanced output w/ various spikes, consistent with your results. I never could find that graph, but I'm sure it exists somewhere. Those spikes happily exist at the frequencies the plants need, even if that never was a design criteria. It really can be no other way.

I strongly suspect that some other MH bulbs may not be nearly as effective for growing, even if the light looks the same to us. I also suspect that the reason HPS bulbs work as well as they do is because they have just enough blue light for the plants to compensate for the lack in ways we don't really understand, either.

I'd love to be able to run a controlled experiment using some of the different lights available. Create 100 clones from a strain that's been dialed in, distribute the 4 dozen best into a dozen identical tent setups. Do that in one big room, feed them all from the same hydro reservoir, just with a different bulb in each tent. Tend them all, taking notes. Save & weigh the production from each tent- stems, fans, popcorn, sugar leaf & top buds. Have a panel of connoisseur testers evaluate each batch. Do it again, just to be sure that the results are repeatable. I strongly suspect that bulbs having more blue than standard HPS would produce better results.

As small growers, it's very difficult for us to eliminate all the variables to establish truly scientific results. OTOH, we can learn from each other, try different things as our circumstances allow. It's also hard to take chances when we have a method that works well, given that we all depend on harvests in one way or another.

I'm pretty much stuck with a horizontal bulb in a vent hood w/ two stage ventilation because of headroom, combined with the technical difficulty & expense of providing AC in our 6 plant grow. I really can't justify it. I intend to rework the whole thing late this summer with a little more room & better ventilation, at which point I *may* be able to add something like a 400w bare vert bulb or a Philips CMH.

Under more amenable circumstances, I'd be all over your bulb selection & methods like a monkey on a cupcake. Your girls are gorgeous.

Really critical points. Subjective observations of "sunlight likeness", intensity, etc. mean nothing at all toward our goals. An experiment like you describe is the only way to get any information approaching useful. Wouldn't even have to use weed - results from a similar plant would be compelling.

Turning this around a little .... Say you are selling a grow light you claim is superior in one way or another. VERY EASY TO DEMONSTRATE. Lack of proof may mean something. Could be that there is no advantage. Could also be that we are a gullible bunch who are as swayed by anecdotes as we are by science. Perfect market for all kinds of snake oil.

 

[tokersmoke]

Really critical points. Subjective observations of "sunlight likeness", intensity, etc. mean nothing at all toward our goals. An experiment like you describe is the only way to get any information approaching useful. Wouldn't even have to use weed - results from a similar plant would be compelling.

Turning this around a little .... Say you are selling a grow light you claim is superior in one way or another. VERY EASY TO DEMONSTRATE. Lack of proof may mean something. Could be that there is no advantage. Could also be that we are a gullible bunch who are as swayed by anecdotes as we are by science. Perfect market for all kinds of snake oil.

I think the science has already been proven.Gnome and myself have run grows with hps only and had less desirable results.Everything in my routine has remained the same besides the light.So scientific no but logical yes!!!

 

[RB56]

I think the science has already been proven.Gnome and myself have run grows with hps only and had less desirable results.Everything in my routine has remained the same besides the light.So scientific no but logical yes!!!

I mean no offense, but this post is a very good example of what I was talking about. You start with the "science had already been proven" then "so scientific no but logical yes". I've been watching forum consensuses on a variety of topics in a variety of fields for many years. Sometimes it's right and sometimes it's completely wrong. That's kind of inevitable whenever a knowledge system is built by anecdote.

We all feel our way toward success. Once things start working it can be very difficult to sort out what mattered from what doesn't. I started adding a teaspoon of food grade diatomaceous earthto every gallon of water. Might add silicone, might accumulate near the top of my pots to create a more hostile environment for insects. Then again, it might not be doing anything at all. I may have just started using it when I finally got things dialed in and so I think it's helping. I don't know but I won't stop until I'm absolutely convinced it isn't doing anything. I'm sure most of us do many things that fit into that category.

I use Digilux MH during flower. I get thrilling results so won't change without real proof but have no idea if these bulbs work better than the generic MH and HPS I used to use. There are so many variables in a grow that it would take an experiment very like what [FONT=Arial, Helvetica, sans-serif]Jhhnn[/FONT] proposed to be convincing.

I think one of the things all of this demonstrates is that cannabis can thrive under a variety of color temperatures and spectrum bands. Everything else being equally, color temperature (within a reasonable range) may be a relatively small factor. We can almost assume it is a small factor since there is no real consensus.

I'm all for testing and experimenting. My only point is that it is much easier to convince ourselves that something is true than it is to come up with anything approaching proof.

 

[Jhhnn]

Thank you, RB56. Logically, theoretically, it seems to me that broad spectrum bulbs would give better results, being more like natural sunlight, the plants natural & evolutionary environment. OTOH, I don't have the scientific data to support anything more definitive than that. What seems to work well for me includes a fair amount of subjective judgment. In my case, it also includes a lack of long term experience. With a small single lamp Colorado legal personal grow & limited resources, they'll invent new bulbs faster than I could test 'em.

I'll probably stick with the dual arc plantmax for the time being. It suits my circumstances, I like the results, and I like the mid range price, too- $61.46, free shipping-

http://www.1000bulbs.com/product/88210/PX-LU1000MHDA.html

I'm sure that the dual arc horti is terrific, but there's no way I'm giving up $259 for a freaking bulb. Nuh-uhh.

Selling snake oil to stoners? Probably easy, cuz they're, you know, *stoned* a fair part of the time. We seem particularly vulnerable to cutesy & evocative naming & branding.

 

[tokersmoke]

I have my enviroment dialed in and have been using the same soil and nutes for over a year. i Have been running the same strains for the same amount of time.The only difference is the bulbs.If i had been changing more things i could see the confusion about what was really causing it.

Either way i see your point.I dont buy snake oil and im pretty hard to get over on.

 

[the gnome]

I think the science has already been proven.Gnome and myself have run grows with hps only and had less desirable results.Everything in my routine has remained the same besides the light.So scientific no but logical yes!!!

tokersmoke, I appreciate your confidence in my abilities...
but thats a pretty big leap to say science has been proven in any way by me or anyone yet on the subject,
as jhnn stated it would be nice to see someone run controlled grows with 100s and 100s of plants using mh and hps
now that would lend more weight one way or the other on the subject.

btw,
glad to have you take an intrest in this conversation RB56
of course with that statement i made that the 4000K looks more like sunlight than any other Mh bulb Ive ran to date also made no claim that its a better bulb because of it,
and what i said about sunlight resembling the 4000K no way implied anything other than just that.
its the visual observation that i made, no more no less.
maybe coincidence
BUT
but my 2 years experience running mh/bloom using various kelvin ratings w/mh has lead me to the conclusion with results that back up my view that the higher blue 6000-7500K bulbs are crap for harvest as stated in this and other threads.
since going to the 4000K I am getting "consistently" better harvests than in my last 4 yrs of indoor growing a opposed using hps horti super eyes,
again...maybe coincidence...?

I think i need to say this, and i had to repeat it constantly in my Mh vs HPS thread because it was turned into which is the Best Bulb for bloom debate by the hps is the only bulb for bloom crowd.
I never tried to convince anyone to use Mh over HPS
Ive not once said Mh is better than HPS,
but i have had to say many many times....
MH strain depending ***is as good in bloom*** as any hps.
sometimes better, and the same can be said for using HPS

what I have said many times is using MH
is **over all as good *** as HPS and at times better.
although that view seems to constantly be seen as such by people dropping into the conversation that I am implying MH beats HPS hands down, i can to a point understand that view as the more people see what I do with a $21 MH bulb the more people want to do what Ive done and I spend a lot of time telling them how i do it.

what i do know for sure is this and I believed it since i started indoor gro's 4 yrs ago
1- HPS is the best bulb for bloom ---->untrue
2-you'll get leafy plants in bloom with MH---->untrue
3- your buds won't be dense using MH in bloom---->untrue



this is my take on it,
and this is what Ive been saying since I started using MH in bloom.
if you like hps and are happy with it... fine
if you like MH and it floats your boat... good
if you see that Mh and HPS combined makes your harvest fine and good... great.

personally MH floats my boat
the more I use the 4000K Mh bulb the positives keep adding up.
my harvests are just as good or better than hps depending on strain.

paying $21.50 per bulb as opposed to $80-$100 for a quality hps super horti is a no brainer

in bloom the stretch I average so far is 8-12" with any sized plant as opposed up to 2+ times the plants height using hps

MH runs cooler than HPS, i save $$ on my Ac electricity.

with mag ballasts there's no need to pay for the hps function
so again --->extra $$ in my pocket

and lastly...
i don't have to deal with that fooking orange light again!

 

[flora420]

gnome, i suppouse you have alot grows behind you with mh bulbs?

if so, you could turn back to hps bulbs for one or two grow's! just make sure you use familiar strains and familiar ways of doing your thing, and if your yield is clearly smaller again, then we can say which one is better.

tho i understand that its propably strain related which one is better, but i assume you have many grows behind you with different strains but yeah...

you should split your growing room in 4 different rooms, with 4 different strains. 2 of them are with hps and other 2 with mh. and between each grow you change the strains completely. then after like two grows you should clearly tell which one is "better". just an idea that i would do if i had the resources. cheers

 

[Jhhnn]

Gnome raises an interesting point about strains. Some indoor strains may have been grown under HPS for enough generations that they're now adapted to that spectrum through grower selection. I doubt it, but it's possible, I suppose. It's tough to overcome millions of years of evolution.

 

[acridlab]

I went and did it, gnome..I was leary of those Sylvanias after u mentioned possible problems with them running horizontally..plus they're pretty Damn big..
So I went with solis tek mh 4000k. Figure I'm running they're ballast, might as well rock the bulb too.. I'm really liking them.. the light is def. reaching further into the plant vs. the ushio hps that were in there prior.. keep u posted.. great thread..

 

[who dat is]

View Image I went and did it, gnome..I was leary of those Sylvanias after u mentioned possible problems with them running horizontally..plus they're pretty Damn big..
So I went with solis tek mh 4000k. Figure I'm running they're ballast, might as well rock the bulb too.. I'm really liking them.. the light is def. reaching further into the plant vs. the ushio hps that were in there prior.. keep u posted.. great thread..

Please do keep us posted on this bulb! I just got some solis teks and was trying to figure out which bulb to get for them. I'm still on the fence about mixing spectrums with my hps bulbs already in there and wanted to get that 4k.

 

[tokersmoke]

ok It seems like i was wrong about the color temp.The bulb im using is 7000k here is a graph

After reading more about the subject it seems that color temp is a measure for our eyes.What the plant sees is totally different.

 

[acridlab]

[URL=https://www.icmag.com/ic/picture.php?albumid=52815&pictureid=1232132&thumb=1]View Image[/url] ok It seems like i was wrong about the color temp.The bulb im using is 7000k here is a graph

After reading more about the subject it seems that color temp is a measure for our eyes.What the plant sees is totally different.

I've always read that lumens were a measure for our eyes, n spectrum is what plants see..
Could be wrong

 

[the gnome]

good news on finding that ushio in the 4000K acridlab.
is it a universal position?
if so i would try it in vert first and note what it looks like then try horiz to see if you get any change.
the $21 sylvies are the 1st Mh Ive seen to change color in the horiz.
of course it's a $21 bulb meant for hi bay lighting
I'm thinking the higher quality grow bulbs prob won't have those issues.

so,.... I'm really intrested in seeing how your ushio performs,
I have some other side projects that require the use of air cooled hoods so that ushio sounds like what I would be looking for.


and yes, lumens and Kelvin are a rating scale for our eyes