"growing plants taller than 12" before flowering is incorrect". Is this true???

Hey hearmenow, just my opinion, but I would opt for buying new, you have no idea how old the bulb is when you buy used. Or any other problems that may arise. For $119.00 you get all new and a warranty too, from a reputable source too. Theres no point in going less than the 400 really, not price wise anyways. (just my 2 cents worth)
Peace

VM, your input is always welcome. I've been reading up a lot on HPS lighting and for my purposes, 150w should be adequate. My goal is to be independent of the dealers or anyone else. I just want to be able to keep the wife and I well stocked. For that I think we'd need roughly 1/2 - 1 oz a month (depending on potency). Maybe I'm naive or overly optimistic but I'm thinking if I harvest 2 plants each month, that should cover it. So basically I think I will be looking at 6 plants in varying stages of maturity or curing at any given point. I will use my CFLs for vegging and then the HPS for flowering. Does this sound like a viable strategy?

"I will use my CFLs for vegging and then the HPS for flowering. Does this sound like a viable strategy?"


just my opinion but get a small mh, youll see faster growth and wont have to hassle with cfls.

Thanks for the advice, Doob.

hearmenow said:

Thanks for the advice, Doob.

Click to expand...

Not particularly good advice though.

A MH will cost you a lot more money to operate and will generate a lot more heat and won't do a better job than the cfls.

Stick with the cfl's for vegetative growth - you don't need a Metal Halide for the space and number of plants you're growing.

Always great to hear diverse opinions. Forces me to read more and expand my understanding. Pretty soon I will be a cannabisologist.

you want to keep plants moving in and out of veg to flower right? that means those cfls you use will have to be on all the time, and you will be needing to replace them often. a small mh light will use up just as much energy as all the cfls you will need and give you better faster, results. i used to use cfls for veg switched to mh and never turned back. there is more heat to deal with but its not over bearing. just my .02

With my current living arrangements (step daughter and 8 year old daughter), I just don't have the space for an elaborate setup. My stepdaugter is supposed to be going away to college this fall, so I'll have her room available to use as a tv/reading room/storage area, so that should free up some of my other storage room for something more elaborate.

"A MH will cost you a lot more money to operate"


not true at all, you can find mh lights as low as 70w

DoobsDay said:

"A MH will cost you a lot more money to operate"


not true at all, you can find mh lights as low as 70w

Click to expand...

Whats the wattage size got to do with what I said? An equivalent wattage MH will cost more to operate than equivalent wattage cfl's because you have the ballast to take into consideration, add in that MH HIDs only out put out about 30% of their light in the correct spectrum compared to cfl's 50% or more and you have a light that costs more to operate as I said originally.

So how is that not true?

Well... like many have said, it all depends on the area you have. I have a 3x3 box so i only plan to grow 3 plants up to 12-14 in tall, then start the flowering process.

dude ive used both and the mh work works better hands down, no debating it. yes the mh light uses more energy then it says when you start it up because of the ballast, but cfls have a ballast to y'know. so lets think 1 mh ballast vs 8(ish) cfl ballast hmmmm. not to mention the mh bulb will last 3 times longer then all them cfls, plus it will not lose as many lumens with age. i found the mh to be more economical then cfls and less of a pain in the ass. sorry you disagree babygro

DoobsDay said:

"A MH will cost you a lot more money to operate"


not true at all, you can find mh lights as low as 70w

Click to expand...

the problem with small MHs is that their effectiveness decreases with size, their optimum of 120lum/W they have with 400-600W only. small MHs can be less effective then CFLs that way.

a 150w mh puts out 107 lumens per watt

a store bought cfl puts out 62 lumens per watt

even the t5's which cost much more then a mh light only put out 95-100 lumens per watt

the only advantage the floro lights have over mh is the one none of you have mentioned, that they can be placed much closer to the tops of the plants.

DoobsDay said:

a 150w mh puts out 107 lumens per watt

a store bought cfl puts out 62 lumens per watt

even the t5's which cost much more then a mh light only put out 95-100 lumens per watt

Click to expand...

And as I mentioned earlier HIDs generally only output on average about 30% PAR. So of your 107 lumens per watt only about 30-35 of them are actually being used by the plant - but you're still paying for 100% of them. CFL's are around 50% - about 30 PAR watts and they're cheaper to operate than MH because they have an inbuilt ballast which is included in their wattage rating - the ballast for MH is not.

As I said - MH are more expensive to operate.

babygro said:

And as I mentioned earlier HIDs generally only output on average about 30% PAR. So of your 107 lumens per watt only about 30-35 of them are actually being used by the plant - but you're still paying for 100% of them. CFL's are around 50% - about 30 PAR watts and they're cheaper to operate than MH because they have an inbuilt ballast which is included in their wattage rating - the ballast for MH is not.

As I said - MH are more expensive to operate.

Click to expand...

i told him that early too, now he came up with the claim, in a other thread about fire hazard, that CFLs are hotter then HPS/MH bulbs...

"and they're cheaper to operate than MH because they have an inbuilt ballast which is included in their wattage rating"

what? that is some bull, as you can find mh and hps lights with an inbuilt ballast, and lol that dosent dictate how cheap they are to operate

"And as I mentioned earlier HIDs generally only output on average about 30% PAR. So of your 107 lumens per watt only about 30-35 of them are actually being used by the plant"

ok nice statement dont know if thats fact or fiction, i dont have any figures on how much of the mh light is used in photosynthesis but ok . you say only 30% or 35 lumens per watt, then you said only 50% of cfls which would be 31 lumens. so according to you only a 4 lumen differnence between a equal mh light and cfl. makes no sense

you cant compare lumens and par like that.

DoobsDay said:

what? that is some bull, as you can find mh and hps lights with an inbuilt ballast, and lol that dosent dictate how cheap they are to operate

Click to expand...

Bull is it? How good are you at maths?

A 200w nlite draws 161 watts of electricity, a 400w MH draws 3.8 amps on a 120v system, 3.8 x 120 = 456 watts. So a 400w MH uses 456 watts and 2 x 161 uses 322 watts per hour. Notice the difference in watts useage?

DoobsDay said:

so according to you only a 4 lumen differnence between a equal mh light and cfl. makes no sense

Click to expand...

That's because you clearly don't understand what PAR is.

DoobsDay said:

you cant compare lumens and par like that.

Click to expand...

No you can't, but you talked about lumens.

Lumens is a light measurement designed for the human eye and bears no relevance whatsoever to what light spectrums plants actually use which is called PAR.

Metal Halide bulbs which output so many lumens are measured using the light meaurement system the human eye can see, the actual light plants use is measured in PAR and as I mentioned HIDs output about 30% PAR light, so 30% of the total number of lumens output is the total PAR The plants actually use.