advise on closet setup and design

so i have a 2x4x8 closet. i want the most yeild i can get in the shortest time which i know wont be much. and i wanna use fluro's because of heat issues. so hydro would probably be best right? what you guys think about i a mini vertical setup vs a regular one. i want to use about 400w plus i'll need a small exhaust and filter just for the smell. what should i do?

Are you familiar with hydroponics???I would recommend ebb and flow system (flood and drain).Simple easy and pretty affordable to make your own set up

If you want to put 400w of lighting in there then you are probably better off with hps, they are almost twice as efficient as fluoros and a watt is a watt as far as heat output is concerned. 400w of fluoros will give off at least as much heat as 400w of hps, but the light output from the fluoros will be more spread out less intense, and about half the lumens.
A vertical system is the most efficient layout in terms of making the most of available light, next is a stadium type grow, followed by the traditional flat grow.

are u sure fluro's produces the same amount of heat at as hps at the same watts? i've never heard that before. i think your wrong if you look at fluros you can touch them with your hand and its nothing but hps after a while you cant do that. i understand that hps produce more light but heat if a top concern because i cant have the exhaust going out to a window or another room.

and ya a vertical setup would be ideal but im thinking how i could pull it of in such a small space, i'll start planning and see how it goes

I'm certain I am right, a watt is a watt is a watt. If it goes in, it must come out, we have established that cfls produce less lumens per watt than hps, so where do you think all that energy goes? That's the thing with all electrical appliances, they are not 100% efficient, and any wasted energy is converted to heat.
The reason you can touch cfl bulbs is because they are small, have you ever seen a 400w cfl? Have you ever touched a high wattage cfl while it was running? Any experienced grower or electrician can tell you that cfls will warm your room if you have them in large quantities. At least the same amount of heat is there, it is just spread around between the multiple bulbs. If you have a single high wattage light source then it is easier to cool than if you have several smaller ones dotted around.
It doesn't make a tiny bit of difference to me whether you believe me or not, I was just trying to stop you making a potentially costly mistake, but I guess some people have to learn by doing, and that's fair enough, I'm a hands on guy myself, but I always try to get the theory of what I'm doing well worked into my head before I start.

fuck there that goes, you think just a fan and a small exhaust would be good enuff take care of heat for 400w?

bob is right they will produce right at the same amount of heat. you may even be cooler with the HID if you remote locate your ballast outta your grow room. i ran 575 watts cfls and switched to 600 hps, my temps are the same.

The size of fan you need depends on the intake temperatures and the size of the room. It's wise to have a fan capable of moving the volume of the room 2-3 times a minute with hid lighting. Your room is 2x4x8 = 64, so your fan should be at least 130cfm, up to about 200cfm, but add 10% if you want a carbon filter or need to run lots of ducting (more than 3-4 feet). A good 4" centrifugal/vortex fan (like this example http://cgi.ebay.co.uk/Elta-fans-SJ-125B-in-line-centrifugal-fan-125mm-dia_W0QQitemZ180375176560QQcmdZViewItemQQptZLH_DefaultDomain_3?hash=item29ff32c570&_trksid=p3286.c0.m14&_trkparms=65:12|66:2|39:1|72:1686|293:1|294:50 ) would be sufficient, stay away from axial fans, often called inline or duct booster, look like this http://www.smarthome.com/3011/6-In-110VAC-250CFM-In-Line-Duct-Fan-DB200/p.aspx and are pretty useless for moving air much further than through a wall. They are fine for free air movement, but don't cope with static pressure at all well.

The ballast on a CFL is what generates the majority of the heat. Fewer higher wattage CFL bulbs would output much less heat than a HID of equivalent real wattage(and including the HID ballast, of course). A bunch of smaller CFLs, each self-ballasted would produce as much, or even possibly more heat than equivalent HID. The higher wattage bulbs have a wider diameter(the glass tube), and the bulb itself is actually cooler than the smaller wattage(also smaller tube diameter) bulbs. Then again, the bulb's manufacturer and color temperature is also fairly critical. I have some 42 watt 6500k bulbs from Feit that operate cooler(overall) than these 'house brand' 26w 2700k bulbs that were really cheap.

And the larger linear tube fluoros(T8/T12) run so cool the plants can touch the bulb without any injury, but the ballasts get somewhat warm. T8's still offer nearly 90 lm/W, and come in plant-specific spectra. Oh, and are a hell of a lot cheaper than T5s.

HID generate tons of IR radiance, fluoros don't. Fluoros generate UV light which excite phosphor coatings which then fluoresce and emit specific frequencies of visible light. A HID(HPS), on the other hand, is basically an improved incandescent bulb, which creates a plasma arc of up to around 1100C(MH is slightly less), which then radiants brilliantly. The surface of the bulb can reach several hundred degrees(well beyond boiling point of water). They don't utilize power or release it anywhere near similarly(a MH is the closest to 'bridging' these technologies, which often utilizes mercury vapors with metal halides, as a MH is basically an improved version of a MV). So no, watts in does not mean watts out. Even MH run slightly cooler than HPS simply due to the spectra of radiance they emit. Less IR, more UV -which can be harmful to humans, but great for trichrome production.

Fluoros(agro/hort HO t5/t8, Gro-Lux, for instance) achieve about 140% of HPS's efficiency maximally(PPF). These fluoros use special phosphors and ion treatment which maximize light output that's plant-usable(PUR/PAR). As a result lumen output drops significantly! Most CFLS are around 65-75% of HPS (again PPF, not lumens! PURple CFLs would be approaching 130-140%).

I've read numerous stories of growers switching to 216W T5 panels(up to 91-92 lm/W) from 175-250W HID, and reporting vastly decreased temperatures(around 5-10 degrees). Plants can basically touch these T5's without being damaged, though an inch or two is the suggested minimum.

These 'high tech'(they've been around for decades) plant fluoros produce as little as half the lumens but a higher level of plant usable radiation(PUR/PAR, measured as PPF) than HID, watt for watt. HID still has vastly better 'penetration'/throw, meaning it has a much wider/further/larger volume(or radiant flux, or photosynthetic photon flux/PPF). Consequently they have a much larger unusable area due to excessive radiant heat near the bulb. Or simply: if you want big, tall, denser plants, HID is the best, simplest solution(400W or better, ideally). If you grow smaller plants, a few feet tops, fluoros are more than adequate, and probably the best, simplest solution.

Also note, doubling your light output will almost always(after a certain point, well below the output of a single 13w CFL) not even get close to doubling your harvest. As the light amount increases the distance between total biomass and total flower/fruit mass increases(meaning less and less bud, and more 'undesired' stem/leaf). And even the total biomass doesn't even nearly double. It's a game of diminishing returns. CO2 supplement and 'advanced' nutrients(either the brand or just any high quality nutrients) will provide better results than simply adding more light.

i have the same size room, i will give you some insight when i have more time.

Thank you for explaining that so well, TeaTreeOil, I knew quite a lot of that, enough to understand the terms you used, but my understanding wasn't as complete as yours.
I really feel I learned something today, thank you very much and +rep.
edit: I do have a small point which is that vented reflectors are widely available for hps lights, which can reduce the unusable area close to the bulb significantly if used in conjunction with a decent venting system, although admittedly that is more hassle + expense.
Question, as you seem to really know what you are talking about on this subject, do you know whether having the bulb separated from the plants by glass (either a flat plate or cooltube) has a negative effect on the amount and/or spectrum of light that reaches them? I read somewhere that the curved glass of cooltubes can refract the light and alter it's spectrum, but I've not seen a satisfactory explanation of how and to what degree. Ditto the amount of light lost as it passes through glass, obviously some is reflected, but how much, generally? I know it'll depend on the thickness and compostition of the glass, but is there a way to calculate it without actually getting a light meter and testing a particular sheet/tube of glass? Thanks for your time, Bob

ya man, great explaination altho i didnt know all the terms i get what u saying. i tend to keep my plants short so i'd go the fluro route and try getting some lighting with an external ballast that can be placed outside the closet. thanx how do u add rep? i dont see any button anywhere

Hairy Bob said:

Thank you for explaining that so well, TeaTreeOil, I knew quite a lot of that, enough to understand the terms you used, but my understanding wasn't as complete as yours.
I really feel I learned something today, thank you very much and +rep.
edit: I do have a small point which is that vented reflectors are widely available for hps lights, which can reduce the unusable area close to the bulb significantly if used in conjunction with a decent venting system, although admittedly that is more hassle + expense.
Question, as you seem to really know what you are talking about on this subject, do you know whether having the bulb separated from the plants by glass (either a flat plate or cooltube) has a negative effect on the amount and/or spectrum of light that reaches them? I read somewhere that the curved glass of cooltubes can refract the light and alter it's spectrum, but I've not seen a satisfactory explanation of how and to what degree. Ditto the amount of light lost as it passes through glass, obviously some is reflected, but how much, generally? I know it'll depend on the thickness and compostition of the glass, but is there a way to calculate it without actually getting a light meter and testing a particular sheet/tube of glass? Thanks for your time, Bob

Click to expand...

You're welcome! Glad to see someone's learning something.

Most glass is fairly transparent when it comes to visible light(over 90%). However, glass can appear quite opaque if you used a thermal imaging camera. It depends quite a bit on the composition of the glass.

Also, the more acute the incident angle is, the more reflective glass is.

The transmission coefficient is what you should be most concerned about. That's the percentage of radiance which goes through the glass without being absorbed, reflected, etc. For most glass this percentile is in the high 80's to low 90's for visible light, and quite a bit lower for IR light.

I would bet that using a hood with a glass-covered opening would be better than having your light further away to keep your plants safe from the heat.

To calculate it exactly you'd definitely need tools to measure the reflection. Usually a photometric sphere is used for such purposes.

Thanks for that clarification, it's pretty much what I expected but it's good to hear it from someone such as yourself who really has a handle on all this.
Do you know if there's any truth in the theory that curved glass can alter the spectrum of light passing through it?

All glass is going to alter the spectrum of light passing through it, regardless of shape, but usually not by more than 6-10% or so(for visible light). UV is transmitted very poorly. IR can be filtered by special reflective coatings, to increase the insulation(R) value. Some compositions of untreated glass let over 90% of IR through. There are also various methods of filtering specific frequencies of light using various coatings.

For example: http://www.pgo-online.com/intl/katalog/curves/whitefl_kurve.html

That's a transmission curve for their glass. While fairly uniform(from 400-2500nm), the entire spectrum is clearly not treated equally, especially UV!

Thanks for all that, you've been more than helpful. Now I just have to memorise it all.