CFL vs HID for 2x4 tent

[Tarkus]

I'm setting up a 2 x 4 Gorilla grow tent. At this point I'm looking for ideas as to what the right lighting setup would be. I'm wondering if anyone here has any first hand experience with this line of products.

CFL, GROW LIGHT SYSTEMS

I'm particularly interested in the 2k watt fixture. But, other than what the manufacturer says about it I can't find any actual customer reviews or comments. I've also considered this:

But I'm not sure if a 600w HID would be overkill for a 2 x 4 tent in terms of managing heat and cost of electricity. The tent would be set up in a spare bedroom with the door closed most of the time. So for the most part the heat exhaust would likely be a problem with no outside ventilation. So it seems like the CFL would be the right way to go in my case. Does anybody here have any wisdom they could pass along about this line of CFL lighting. It looks awesome, but then that's what marketing is supposed to do. Thanks in advance.

 

[AfricanGrower]

Hey there Tarkus, I'm also having the sasme dilemma on which setup to go with. My restircitions mainly have to do with electrical costs of running a HID system since my monthly bill will be monitored. All in all I have read a couple of articles on here that show the potential of both systems producing amazing results. HERE you can see the potential of high wattage cfl systems producing some pretty dank buds, but I have been inclined to the fact HID might just give a little more density and weight output for an end result, but I'm no expert

I am currently waiting on a reply from a reputable grower on these forums called TheCapn, and based on his grow techniques he optimizes his 10-20oz yeild per plant with a 400watt MH/600watt HPS system that seems to work wonders. I still want to know if he thinks a cfl setup with same amount of wattage (smaller dent in the electric bill) would produce the same amount in yield. You can find THeCapn's setup HERE with tons of helpful articles in his sig.

That being said are you looking to go with a hydro or soil setup? How many plants?

 

[Hosebomber]

There are a few things that may help you make your choice. First, CFL lighting is less efficient than HPS or MH lighting. This means 2 things, It requires more input wattage to get the same results and that it produces more heat to produce the same amount of light output. It doesn't matter what type of lighting you use, if you draw 400 watts of power it will increase your bill the same if it is HID lighting or CFL. Read over the link in my signature for more basic information on plant lighting.

 

[Tarkus]

Holy crap!! 10-20 oz/plant. Well I really don't have a good frame of reference but that seems pretty incredible. And I did read that thread about CFL lights. What I took away was that CFL can be a viable light source, but all else being equal; the HID set up is superior at getting the desired results. But I have no means of quantifying that difference to be able to judge whether it would be worthwhile. I'm sort of looking at it as a trade off. I can put up with the extra heat and higher power bill and get a better yield, or use a less effective but cooler CFL setup that costs less to operate, at the cost of some productivity. As hosebomber points out, CFL becomes less efficient as the grow area increases. In my case that would be 8 square feet. Not alot. The CFL set up I'm looking at

is 3' x 20". In a 4'x2' tent the fixture alone would take up over 65% of the surface area. For what it's worth they claim the coverage area is 8'x6'. So if surface area is more of a limiting factor for CFL, then it doesn't seem like it should be a concern in my case. But then what do I know? Otherwise I wouldn't be asking.

But if I were to go the HID route, my question is still whether 600w is overkill for a tent that size, or if a 400w would make more sense. I do have a 400 cfm fan/filter combo if that helps.

To answer your question, I'm leaning toward a hydro setup. I just need to make sure I know what I'm doing first.

 

[Graytail]

I think 400 watts is perfect for that size tent - that's 50 watts per sq ft. With that much light, you can grow fine cannabis.

If it were me, I'd check out the price difference between a 400 and 600. The 600 is more efficient, and with a dimmable ballast, you can turn it down to 450 and 300 watts. It's never a bad thing to have too much light.

I built my own 483 watt CFL rig, and if I had it to do again, I'd have skipped the CFLs. I replaced them with a 600W hps after 45 days. CFLs are dynamite for sprouting and vegging, though. I'd advise against the "2000" watt CFL rig. It's only 460? watts anyway, and as Hosebomber said, it'll produce as much heat as a 400W HID.

 

[AfricanGrower]

>>> I'm sort of looking at it as a trade off. I can put up with the extra heat and higher power bill and get a better yield, or use a less effective but cooler CFL setup that costs less to operate, at the cost of some productivity.

For the trade off you can look at it this way: The HID setup would only require you to ventilate heat away from one bulb versus the CFL' setup with 20 bulbs generating heat. As you said the CFL setup would cover most of the tent meaning more frequent heat build-up even though they produce less heat in comparison. If the higher electric bill is not a concern, IMO I think you would be better of with an HID setup to go along with the 4x6 tent.

>>>But if I were to go the HID route, my question is still whether 600w is overkill for a tent that size, or if a 400w would make more sense.

I agree with Gray on this one, the 600watt dimmable balance would be a great investment, especially if you planned on upgrading your grow the next time around.

>>> To answer your question, I’m leaning toward a hydro setup. I just need to make sure I know what I’m doing first.

Yea it is going to be my first time growing hydro aswell. I was thoroughly convinced by TheCapn's articles that it would be worth while
Just a thought, if you were to go with the CFL setup, using up to 65% of the grow space, I would think you will keep the your hydro setup smaller than average. How much yeild are you shooting for for this grow? Do you have any specific time frame you need to complete this by?

Sorry for all the questions, I am just trying to get a broader range in perspective when it comes down to starting mine!

 

[hoopgang]

Just a warning, I read that if you dim a hid light it does change the spectrum and can also reduce the lifespan of your bulb, the spectrum change is larger in mh than hps. From my own experience using a 600w hid I'm having a lot of problems with temp. And haven't been able to bring the bulb as close as I want to the plants or fully enclose the space wiith reflective material because of this. I have no active ventilation just a few fans and a window to blow air out of and just a simple wing reflector hood. I think you could get away with no active ventilation in the fall or winter but summer would be very very hard. I would recommend getting either a cool tube or air cooled hood though if you do go hid.

 

[Tarkus]

>"How much yeild are you shooting for for this grow? Do you have any specific time frame you need to complete this by?"<

Since this my first attempt, I don't have any frame of reference for setting a goal on the yield. To begin with I've never really had a knack for taking care of plants. I always figured plants came to my place just to die. So if my plants manage to survive at all, I'll take what I can get at this point. No particular time frame either. Again, no frame of reference. I have to start by taking my baby steps, and we all know that babies stumble and fall a lot at first. I'll be finding out soon though. I went ahead and pulled the trigger on that 600w system from Amazon. From what I've been reading, the overall consensus leads me to believe HID is the way to go. The dimmable ballast was a big factor in my decision. At least that gives me some control over the heat. Where I live the summers can get into the triple digits. So I really don't want the additional cost of running the a/c because of the added heat from the light, on top of the expense of running the light itself. I’m doing this all for personal consumption. So maybe the way around that is to grow enough yield during the winter months to last through summer.

So my next big decision...soil, or hydro? Who knows…by the time I'm through anguishing over everything that goes into this, it'll be winter time anyway.

 

[Tarkus]

>"I would recommend getting either a cool tube or air cooled hood though if you do go hid."<

The system I ordered does have the air cooled hood. Otherwise I wouldn't have even considered it. So the heat will be vented out of the tent but into the room, which is a spare bedroom. There is no ventilation out of the room other than into the rest of the house. That's fine when the house needs heating, but not when you're trying to keep it cool. As far as dimming changing the spectrum, I guess that means I need to go all out all of the time. If that's the case that would pretty much limit me to the winter months anyway. I was hoping I could use the MH on low power to start the vegging process and work up from there. Is that a bad idea? And why the heck would they provide a dimmable feature on the ballast when it has a detrimental effect on the spectrum and bulb to begin with? Makes no sense.

 

[Hosebomber]

The change in the spectra is minimal at best. Don't worry about that as a factor in anything concerning your grow. As for the cooling issue, you may be able to vent your hood straight out of the window in the room. That depends on your states legal status and how much you want people to know, as well as placing a carbon filter on the vent prior to exit.

 

[AfricanGrower]

Nice choice on the 600watt system Tarkus! As for a dimmable ballast reducing bulb life and changing spectrum, I have read up on some topics relating.

"When a clear metal halide lamp is
dimmed to 50% of rated power, the CRI value
may drop from 65 to 45 and the CCT may
increase by 1500 K. When a coated metal
halide lamp is dimmed to 50% of rated power,
the CRI value may drop from 70 to 60 and the
CCT may increase by only 400 K."

I know some lamp manufacturers warn that dimming a MH bulb lower than 50% capacity could reduce the lamps light by a lot, but when it comes to HPS, I read that you can effectively give the bulb a longer life by starting the system at full power for about 10-15m then dim the ballast down. Just a thought

>>>So my next big decision...soil, or hydro?

Since you this would be your first grow, I say soil only because it is far more forgiving in my experience with it. I started off using soil, and I plan on making my first hydro grow with a journal to go along with it on here!
But don't let me stop you from going hydro, because I've seen pretty successful first time grows, and 'baby steps' is what you are looking for they are plenty of good 'beginner hydro' setups on here I could link you to

 

[Tarkus]

>"As for the cooling issue, you may be able to vent your hood straight out of the window in the room. That depends on your states legal status and how much you want people to know, as well as placing a carbon filter on the vent prior to exit."<

Unfortunately venting it out of the window is not an option. I live in suburbia. Something like that would not go unnoticed. And I have no intention of cutting a vent hole my bedroom ceiling just so I can grow weed. Also, the state that I live in is not cannibis friendly. So I guess altogether that just means the door to the room has to stay open. This also means having to put up with some fan noise. I see they actually have fan mufflers. So I'll have to check into that.

>"Since you this would be your first grow, I say soil only because it is far more forgiving in my experience with it. I started off using soil, and I plan on making my first hydro grow with a journal to go along with it on here!
But don't let me stop you from going hydro, because I've seen pretty successful first time grows, and 'baby steps' is what you are looking for they are plenty of good 'beginner hydro' setups on here I could link you to"<

Sound advice. At my current skill level I'll probably need all the forgiving I can get. I guess the idea of doing hydro seems more exciting to me. But maybe I should save that excitement for another day. I don't know yet. I'm going to have to give it a lot of thought.

 

[Voltrom]

OverKill. Most deff, I haven't read the whole thread but a 150w or a 250w would probably work. Some 250w models have a special fan you can buy to suck out the hot air. Would be a good veg machine.

 

[Voltrom]

A 600w hps in a 2x4 in which your describing would kill anything in it. The heat would be too much to handle. Even a 400w IMO would be too hot unless you have some efficient air exchange.

 

[Tarkus]

>"A 600w hps in a 2x4 in which your describing would kill anything in it. The heat would be too much to handle. Even a 400w IMO would be too hot unless you have some efficient air exchange."<

Now you're starting to scare me. Keep in mind it's a vented hood. It will be hooked up to a 6" fan/filter combo @ 400+ cfm. Wouldn't that be enough? From what I understand, you don't really feel that much heat around the light itself when it's vented like that. The other part to consider is that the tent is 7' tall. It can be raised to 8' if need be. So that should allow for more effective cooling. Dammit, I hope I didn't screw up. Say it ain't so!

 

[Graytail]

It ain't so.

 

[Tarkus]

Thanks Gray. I needed that.

 

[Voltrom]

I had no idea your ceiling 7 feet, you shouldn't have a problem at all lmao.

 

[Voltrom]

But you say you aren't going to vent outside? Your just gonna suck the air out of the tent and back into the room? Ambient temps are crucial, I have a 250w in my room and the temps get around 82F and that's with a fan in the window 24/7 on.

 

[Tarkus]

The door to the room will have to stay open to the rest of the house to help prevent heat and O2 buildup. Like I said earlier, the downside to doing that is the fan noise is more noticeable. As it is now, it sounds kinda like someone left the vent fan on in the bathroom. Not all that annoying, but noticeable. For some reason though I get the urge to take a dump every time I hear it running. I figure a fan muffler should help out.