my plants are just over a foot tall now, and september 10th will be day 40 of veg, so i think i may switch to 12/12 at that point. they should be close to a foot and a half by then, so at that rate, i figure they'll still be a manageable size after a couple months of flowering. you can see what they look like now in the link in my sig below.

i have been searching the forums and have found some discussion about using mh instead of hps for flowering. from what people are saying, it sounds like hps will grow a larger yield, and mh will produce smaller buds, but they may have a higher potency because of the higher uvb of mh increasing thc production. some people use both bulbs simultaneously, but i am thinking about just continuing to use my 400w mh.

there seems to be no shortage of theoretical opinions from growers, but i'd love to hear from anyone who has tried both and compared in order to see what the real deal is... in particular, i have seen that cloudflyer has some nice looking stuff that's under mh.

later taters

__________________
cheers ~LoveIt
check out my current somango/ww grow! (and don't forget my 1st bagseed grow journal- cured and in')

If you have a look at my thread called crossing a triploid male,i have exclusively used a 400watt hps for veg and flowering so you will be able to get a good idea of what you can expect,unfortunately i only have a crap camera so im going to buy a magnifying glass next week for some better close up shots

__________________
http://www.rollitup.org/marijuana-pi...ex.php?u=19179

The hps will give a bigger tighter more resinous bud. The blue mh keeps the plant veg tighter and less spaced for compact growth. I use enhnaced spectrum bulbs that have 30% blue in the hps bulb to help compact the plants but if you have only 1 or the other to use use hps.If you have an mh ballast get a conversion bulb to get hps from the mh ballast.

Not to hi-jack but since this is a MH vs HPS thread I would like to ask a question to anyone that runs both. I have run HPS from the begining and would like to know;

How does the heat heat each produces compare ? Is one hotter than the other ?

Edit; Well I just noticed the OP, who happens to be the person I had in mind when asking the question.

Both put off similar heat. I never seem to have much heat from my units maybe raises air temps 5-8 degrees but I grow in minimal 8 x 8 x 10 areas.

this is the bulb i have... just google searched for some reviews and didn't find any, but it seems like this has a good amount of red spectrum light in it...







Now! Halide and Sodium in one super bulb! The incredible new AgroSun Gold has 49% more red spectrum than ordinary halide bulbs while maintaining super bulb brightness.AgroSun Gold provides the full spectrum of light for healthy plant growth, with more red spectrum than any other halide for increased fruiting and flowering response.

__________________
cheers ~LoveIt
check out my current somango/ww grow! (and don't forget my 1st bagseed grow journal- cured and in')

two rearchers posed as university student studying medical pot, talked to researches of phillips and one other company,the resarch showed that both lights pretty much yielded the same though out testing with hps showing a slight improvement.it was reported in a 2005 HT issue.they also reported that hps holds its intensity for a longer period of time.

thanks for chiming in- that's actually really cool info. so, mh vs hps yielded roughly the "same". i'm gaining confidence about using my mh light for blooming, but my question is: the same what? hps showed a slight improvement, but in what? yield? by "yield", i assume we mean SIZE of yield, not yield in terms of POTENCY of thc, which is what i'm really trying to find out here. the question is: does mh make buds STRONGER IN THC than an hps light, even though we know an hps light makes buds bigger/denser/whatever, and maybe that's the way everyone likes to do it, because that's what everyone has told them is the right thing to do... i'm talking about potency people, not "one light yields 'better' (meaning bigger/denser) than another"... a nice, big, beautiful bud is what one is often (not always) trying to grow when they SELL weed, but the psychoactive effect is certainly the fundamental thing we're ALL after when we SMOKE weed, right?

it makes sense that (on average) most people who grow for the purpose of income are interested in high yield, even if it means the potency is less strong than it could be. that's not what intrigues me... i want to know if i choose to use my mh "agrosun gold" light (which has a good amount of hps- red spectrum- light in it) for flowering, if there is anyone who has actually documented, or at least has some sort of anecdotal opinion that's based on experience, having used mh for flowering (and hps, separately), and is able to describe their findings regarding potency.

__________________
cheers ~LoveIt
check out my current somango/ww grow! (and don't forget my 1st bagseed grow journal- cured and in')

Well if people can flowers with CFLs you can CERTAINLY flower with MHs... Not the right spectrum but as long as it provides enough lumens for the space you're going to get bud. Not optimal but good enough for average growers.

You can flower with MH lamps, and it would be best to use the enhanced spectrum lamp, but if you have a choice, the Sodium spectrum is better for flowering, and an HPS lamp puts out more lumens/watt than Halide. Also, Halide lamps put out more heat than Sodiums.

HTH

__________________