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Lights Ordered: What Config? 8 x 4 Foot Bulbs. Help?


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Old 09-27-2011, 10:58 PM
CrossOps CrossOps is offline
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Default Lights Ordered: What Config? 8 x 4 Foot Bulbs. Help?

Guys, I have lights on the way, its 8 bulbs that are four feet each.

Lumens: 40,000 total
Lights: T5HO (6500k)
Wattage: 540 total watts

I am able to substitute some 3000k bulbs in place of some of the 6500k bulbs. Should I do this, and what ratio? This is for tomatoes, peppers, cukes, etc.

Essentially, I can either put in 6500k or 3000k bulbs, 8 positions. Want feedback before I confirm the order.

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Old 09-28-2011, 12:14 AM
GpsFrontier GpsFrontier is offline
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Here is a link that explains the florescent light spectrum's: Color and Mood : ENERGY STAR

P.S.
I don't know what your paying for the T5's to order them, but here I can get them at Home Depot and Lowe's. I forget which has the ones I was looking at, but a twin 4 foot long T5 light fixture sells for about $35, and that includes the bulbs. But they have 2 and 3 foot fixtures as well. Also Wal-mart usually has even cheaper prices if you can find the fixtures you want. I was looking for twin 4 foot T8 fixtures and found them at Wal-mart for $10, I'm sure you could find T5 there too.
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Old 09-28-2011, 06:51 AM
CrossOps CrossOps is offline
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Thank you GPS. I received them at a price I couldn't really pass up. My question is, how many of those 8 should be 6500k, and how many of those 8 should be 3000k?
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Old 09-28-2011, 07:54 AM
GpsFrontier GpsFrontier is offline
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That's why I posted the link, so you could decide. I could easily say 50/50%, but there are too many variables to consider. Some are I have no idea how many plants you plan on growing, how far away the foliage will wind up being, how you plan to distribute the light etc.. From your post you plan to grow 3 large type plants (tomatoes, peppers, cukes). That would have me concerned with the minimal lighting (4 twin fixtures) you posted that you plan to use (even growing only one of each plant). That may do fine while the plants are young, but good luck growing those large (light incentive) plants to maturity without more light.

Bottom line, the amount of "light intensity" is much more important than the spectrum (especially with florescent lights, as well as the plants you mentioned growing). Typically blue spectrum (natural daylight spectrum 5000-6500k) focuses on foliage, and red/orange spectrum's (warm white, 2700-3000k) focus on flowering for florescent lights. But that isn't always the case, or even important with florescent lighting. The light intensity (how much light you provide) is much more important. Especially for plants like tomato's, cukes, and peppers that require much more light to do photosynthesis than non fruiting plants, and those plants don't rely on the spectrum of light to trigger fruiting. Their continuously fruiting plants. Witch means they grow fruit all season long (regardless of the suns light spectrum during the season).

If it were me, I would probably use all 6500k lights, unless I was sure I had enough light intensity (all around the plants) to grow the plants to full size. Then I might use 50% 6500k, and 50% 3000k for continuously fruiting plants like peppers, tomato's and cucumbers.
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Last edited by GpsFrontier; 09-28-2011 at 08:01 AM.
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Old 09-28-2011, 08:08 AM
CrossOps CrossOps is offline
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Quote:
Originally Posted by GpsFrontier View Post
If it were me, I would probably use all 6500k lights, unless I was sure I had enough light intensity (all around the plants) to grow the plants to full size. Then I might use 50% 6500k, and 50% 3000k for continuously fruiting plants like peppers, tomato's and cucumbers.
Thank you GPS. The lights did not cost me anything (swapping for sidework that take me an hour at most), so I went ahead and put the second request in for two sets of these based upon what you stated. Your a wealth of information GPS, many thanks. I tend to like to ready and study what others do, and then learn from it as I set it up.

The twin setup would essentially put me at 80,000 lumens, or 800 watts to start. I suspect that would be sufficient.
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Old 09-28-2011, 05:13 PM
GpsFrontier GpsFrontier is offline
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When you say 8 bulbs, I don't know if that's 8 light fixtures with one bulb each, or 4 twin bulb fixtures (two bulbs each). Also you mention 540 watts, as well as 800 watts. 540 divided by 8 comes out to about 68 watts each. That seems like a lot of wattage for one 4 foot bulb. The T8's light's I plan to get are 32 watts per bulb (64 total watts for a twin light fixture), but I never checked the wattage of the T5's and I guess it's possible their twice the wattage of the T8's.

But any witch way I simply cant say if 540-800 total wattage of florescent light is enough for your planed setup. It not just the wattage, it's how evenly you can distribute the light around the plants. As well as not allowing the light source (bulbs/fixtures) to be to far away from the plants foliage (hopefully no more than 18 inches away). The more light sources you use, the more evenly you can distribute the light around the plant/s. But the florescent lights still should be close to the plants foliage or the useful lumens will drop significantly, thus not do the plant much good (wasting your wattage/lumens). So your light array/configuration is extremely important to how well the florescent lighting will do for you.

To compound the issue of florescent lighting, you plan to grow three types of large bushy plants that continuously produce fruit. Even if you only planed to grow one of each, they get large and bushy (unless you trim the heck out of them). That makes it more difficult to evenly distribute the light to all the foliage. Even if the plant has a lot of nice looking leaves, only the leaves that are getting sufficient lighting will be able to do photosynthesis. It's just like having a lot of solar panels on the roof, the ones in the shade wont be doing much good. You would want to put them all in a place they get enough light or they wont be doing much good.

Usually I would say if you will be using 800 watts of electricity anyway, you would be better off using 2-400 watt, or 4-200 watt (for better light distribution) HID lights. But I can certainly understand if you are getting the lights for practically free. I wouldn't pass that up either (no mater what). Heck, with that many florescent lights, you'd be able to grow enough lettuce for everybody on your block.
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Old 09-28-2011, 05:58 PM
CrossOps CrossOps is offline
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Hey GPS, thank you for the reply. I made a serious typo on my number that you re-posted, sorry about that.

I am getting two light kits. Each light kit is four feet long, and has 8 bulbs. Each kit puts out 400 watts (40,000 lumens at 6500k). I would assume that's 50 watts per bulb.

Essentialy with both light kits running, there will be 16 total lights equaling 800 watts (80,000 lumens) that can be raised or lowered. My area that I am setting up as a testbed display is 3 feet deep, 5 foot high, and 8 feet long.

It's hard to say if that amount of light is sufficient, but I know your experience, and I trust it based upon your history. As this is my first setup, its definitely going to be an interesting experience. I do however want to make it clear that I respect, and listen to all advice given.
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Old 09-29-2011, 01:25 AM
GpsFrontier GpsFrontier is offline
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Hey CrossOps,
Thanks for all the confidence and trust in me, but I'm really just one guy, with one guys opinion/s. I always like to hear other peoples experiences, that's really what helps me learn too (especially what I can't afford to do myself). I usually try to give a useful reply to help people out when I can. After all when I was just starting out I was hoping for useful reply's to my questions, so I know what it's like hoping for a reply (I just want to help others out). And based on the past three years or so, most of the questions I hear aren't really new questions. But their from new people, or asked in a new way, or with a twist. But never be afraid to ask any question, the only dumb question is the one that was never asked. It simply cant hurt anything to ask (even if you know the answer, and are just looking for a second/third/fourth opinion).

That dosen't mean I always know the answer (or anyone else will reply either), but because of the research I have done this past 3 years, I can usually at least point you in the right direction to find the answers your searching for. Also I wish more people would chime in with more opinions too. Like I said, that helps me learn and provides a different perspective, and that helps us all learn. So I always want to encourage others to give their points of view (and many of them).

All I can really hope for is that many people continue to use the forum (it's not even mine) to share their experiences and knowledge with the rest of the forum community. The more the better, but typically people just gain enough knowledge that they don't really need to ask questions (or know where to get the answers they need), then they slowly stop logging in and sharing with the forum anymore. I guess that's why I try to answer questions as soon as I see them, I hope that will draw in more users because the questions were replied to quickly, then some of those users will become "long term users" that can share their experiences with us well after they gain experience from what they know and have learned (thus, others and I can all learn more together).

Now that I know one of the important factors of your planed grow space, the size of the space you want to grow in. Five feet tall, eight feet wide, and 3 feet deep (120 cubic feet), I would clearly say that 16-4 foot T5 lights would be plenty (even if you were using T8's). Though it sounds like there is only 2 light fixtures for all the bulbs. That will make it hard to distribute the light evenly (from the sides and bottom too). But typically I would say one twin T5 or 8 light fixture placed every two feet would be sufficient. And if the fixtures were placed vertically, rather than just above the plants, that would provide better coverage to the lower leaves of taller plants when placed vertically (and very important for good coverage and plant growth).

Here are a few videos of the best setup for using florescent lights on tall plants that I've seen. The videos are from a member of this forum (not my videos), and what I would try and copy if I planed to use florescent lighting for tall plants. Notice how the light fixtures are placed vertical, as well as evenly spaced around the plants.

hydroponic grow room update - YouTube
Video 7.wmv - YouTube
2/2/2010 grow room update - YouTube
april grow room update - YouTube

P.S.
Considering the 5 foot tall space your working with, I can only assume either your unfamiliar with the size tomato's and cucumbers get, or you plan on using small bush varieties, or you just plan to trim the heck out of them. Peppers most likely wont be that bad in a 5 foot tall space, they will probably get about 4 feet tall unless your using Indeterminate varieties (like most greenhouse varieties), then they can grow 10-15 feet tall. Tomato's and cucumbers will grow 5 feet tall in just a few weeks (given the right conditions), unless your using small/miniature bush varieties
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Last edited by GpsFrontier; 09-29-2011 at 06:01 AM.
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Old 09-29-2011, 01:57 PM
T'Mater T'Mater is offline
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Plz post some pic's when you get your set up all done. I attempted the indoor thing. And when it was all said and done i just moved my setup right outside the garage and got instant results.

I got my tomato plant's to grow like weeds, it was getting them to produce flowers that i seemed to have the most trouble with.

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