light bright

[whiff]

I have read conflicting findings regarding when and where to use HPS and MH. Some say HPS can be used for the entire life cycle of the plant, while others tout MH as the choice for vegging, and HPS for flowering? I just got an HPS, thinking the former to be true. Any good news?!

[NPK]

I think the concensous among many 'gurus' has been swinging toward hps right through over the last few years.

Other people have commented that while yield may be better with hps only, quality, they think, may suffer.

I myself have only ever used hps so can't help any more than that.

seems to work ok B)

npk

[Wilbur Nutsack]

MH gives off a bluer light. More suitable to vegging, but is also used for flowering.

Most folk use HPS for flowering as it gives higher yields. MH increases potency but gives lower yields.

The ideal ratio is 2:1 HPS:MH.

HPS can be used throughout the entire cycle, but for vegging, is a waste of energy. Cheap Flouros will do the job of vegging just as well, if not better.

Wilbur

[NPK]

HPS can be used throughout the entire cycle, but for vegging, is a waste of energy. Cheap Flouros will do the job of vegging just as well, if not better.

Not sure I agree with this wilbur. How much flouro (wattage) do you mean. My plants take off when I put them under the hps during vegging.

Flouros are much less efficent than a 600w hps. So 600w of flouro would Produce less light and create more heat.

If someone has a hps with nothing flowering under it then it may as well be used for vegging IMO

npk

[whiff]

I have done extensive research on HPS and MH, and still have yet to get a str8 answer in regards to lighting requirements for plants. It seems that many will swear by the HPS for all lighting needs, while others use MH for the vegging portion, and then, in turn, HPS for the flowering. I have gone with the latter choice: as it turns out, HPS tends to be a bit heavy in the red part of the spectrum (around 2100k, in contrast to 5000k + of the MH) , which the plant uses, but not effeciently during vegging. I just bought a 400 watt MH for 85 bucks on ebay.

[Wilbur Nutsack]

Given that Whiff is growing in a pretty confined space, i thought flouros to be as good.

He's growing in a pretty long narrow space (4x2) with a 250W HPS. I would think a bank of flouros would cover the area better.

For a larger grow, i agree, HPS/MH will penetrate further than flouros.

I find under my HPS, young plants/seedlings/clones tend to strech like crazy because you have to have the HPS so far away.

I guess theres just not enough blue. I'm not using a mixed spectrum though (grolux, plantastar etc).

What type are you using NPK?

Ballast permitting, i suppose Whiff could spend £30 on an MH bulb to use throughout vegging.

Wilbur

[NPK]

Hi wilbur

I'm using a 600w Silverwing from Growell with a Sylvania Growlux bulb.

I've adapted it to be air cooled with the addition of a 'Bake a round' Glass tube so I suppose I can keep it closer than some peeps.

To be honest I like stretch as I grow SCrog but even before I did the stretch never seemed that bad.

In the long and distant past I used to use nothing but flouro's (10 * 40 w) for my grows and as I remember it the growth during veg was nothing like what I get now.

I should point out that I had very little clue what I was doing back then so that might be why

It's just my opinion but I think if you've got the hps, and its doing nothing, then you might as well use it.

Maybe supplement with flouros if worried about the spectrum.

I toyed with the idea of getting a MH bulb for veg but some things I read put me off.

I'll try and find some threads to link to, I think they were on Cannabis World mainly.

It's always hard to be sure about these things in the absence, for obvious reasons, of any large scale scientific tests.

npk

[NPK]

Not the one I was looking for but interesting none the less

http://www.cannabisworld.com/ubb/Forum1/HT...TML/000126.html

Another

http://www.cannabisworld.com/ubb/Forum1/HT...TML/000112.html

Of course they could well be wrong !

Wish I had a warehouse and a licence to research this properly B)

npk

[Percy Thrower]

I probably shouldn't be posting a reply to this question as my knowledge is very limited,I'm still in the planning stage of my growroom,.

I've been reading plenty of books, I haven't got them here now but can remember some, one stated fluro's where better for seeding and cuttings as they grow small and bushy. and also for a mother plant, I got four books all fairly recent publish dates, and they all recommend hps all the way though, except for keep a mother plant and cuttings they recommend fluro's, if you want me to I'll look at them again and let you what they say.

hope I haven't made my self look like a complete idiot.

cheers

[Joolz]

I use a Silver Wing 400w with a grolux tube for vegging and then switch to a Son T lamp for flowering

Seems to work ok for me

[whiff]

I got my 400 watt MH yesterday from an ebay purchase and wasted no time to hook it up. Got the closet door cracked just enough to allow cooling air from the outside, and my little propane camp light wafting C02 and moisture! What a difference it seems to be making this early in the game! I am really excited: A MH and HPS, both less than an expensive set up combined! B)

[Unit]

Propane camping lamp? Co2 and moisture (and warmth I guess)? Please explain more - I have one, should I be using it?

[whiff]

Propane camping lamp? Co2 and moisture (and warmth I guess)? Please explain more - I have one, should I be using it?

In my mentally and financially-challenged (the later still holds) grower phase, I was actually using my dogs and candles in the evening: I had everyone locked up in the small confines of my computer workroom for a couple of hours a night. In my estimation the amount of CO2 might have been just slightly above neglible, but still, it was cheap.

I am now in my more analytical phase, and am looking into boosting growth through tweaking the various inputs, hence, my current interest in the CO2 discussion.

Okay, here is my scoop on the propane camp light thing. First, the really expensive--and estimably better--generators use either natural gas or propane. Both fossil fuels burn extremely clean, given enough O2--which should be very easy to furnish (ie: my crack of an opening to my walk-in closet). The by-products of both fuels are: (1). Heat-which can be good if you have a cool surrounding area, because notching up the temp., among other things, will increase C02 metabolism; (2) moisture, and: (3) Carbon dioxide. The molecular model for propane is something like CH3-CH-CH3, because carbon has four attachement points (as I learned from organic chem.)

Now, if you look at propane above, you can see where the H2O and CO2 might come from as the fuel is burned with 02....

Okay, so I am on a ritalin rant (really, I am, I have ADD )

To make a long story short, let me say this to you, and damn me if I am wrong.

Get out that Propane camp light, and crank it up. Two words of warning: first, turn it up really, really low. This way, the propane will last much longer, and produce less heat). Secondly, and very important, do not attempt to operate a propane camp light unless you have proper ventilation around you, and never operate one while away from your dwelling--unless you have a damn good excuse for why your home, apartment burned to the ground.

Lastly, keep a thermometer where it can be easily read without having to open the door or what not.

I have to be realistic and say that the C02 my propane light is producing is probably in the milliliters/hour, maybe marginally better. This ain't an exact science, but I figure it is cheap, and it beats having the dogs in my computer room, chewing up my literature.

I am looking to buy a C02 gas cylinder and regulator real soon for my "gas trickling needs" B)

[UFO]

Hi to all,

i was always led to belive that imitating the seasons was the key, by this i mean the light in spring, summer and autum, spring tends to have more balanced light, which increases in the blue spectrum as the sun climbes to it's highest point

(21st june) the ratio of blue wavelenght w.r.t red then decreases over the latter half of summer, with the red spectrum being more dominant in the autumn.

(when the sun is low the light has to travel through more atmosphere which filters more of the uv/blue spectrum...er..i think )

anyway...that's the model i designed the growroom round

i suspect there are many things that influence a persons desision

when using a light (other than yeild) such as heat o/p, growroom height, dosh, extraction, room etc.

i have grown with just hps and all was well, but i got better results with a combo of both, but that also increased the wattage in the grow... so you would expect more bud this gets me onto yeild, how do u calculate it?

i can see no other way other than weighing all of the veg when dried, then weighing the buds and finding the ratio between the two (anybody agree/disagree with this?.)

for what it's worth, i agree with NPK, if you can use them all without it getting too warm, and not burning the tops go for it

just me 2p's worth

UFO

[sittingrelaxing]

i can see no other way other than weighing all of the veg when dried, then weighing the buds and finding the ratio between the two (anybody agree/disagree with this?.)

i grow with a 400W grow-lux and get, and expect at least 1g of good bud per watt .....extra's a bonus.....

(from cuttings)

sr