User Tag List

Informational! Informational!:  0
Likes Likes:  0
Page 2 of 3 FirstFirst 123 LastLast
Results 9 to 16 of 22

Thread: Light Challenged

  1. #9
    Veronis's Avatar
    Join Date
    Dec 2007
    Location
    Harrisburg, Pennsylvania
    Posts
    417
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I'd recommend 6500K shop lights (highest lumens & CRI possible) - heliamphora are tropical I believe, so you *might* do better with 5000K, you'd have to check with someone who knows more than me. I use T12 bulbs, and with those you'd want at least 75 CRI, 84 would be better. Lumens at least ~2850 each bulb - 40-watt not 36-watt - and only get the brand name bulbs (e.g. Sylvania, GE, Phillips), as the generic ones start losing lumens rather quickly.

    For temp issues, I've found that setting up a small fan to blow in between the lights and the top of the terrarium drops the average temp by up to 5 degrees or more, depending on how much the lights are affecting your terrarium's temp in the first place.

    I got a 80mm computer fan (don't get the computer fans at radio shack, way overpriced), cut its computer connector off of the electrical wires, then got a 12V plug at radio shack, wired the fan to the 12V adapter plug (butt connectors & black electrical tape), and plugged it into the wall. The fan I got for $8 from a computer store also came with an adjustable fan speed, so I can basically control the temperature in my terrarium to an extent by adjusting the fan speed.

  2. #10
    Someday is not a day of the week. Maxx's Avatar
    Join Date
    Aug 2007
    Location
    South-ern California
    Posts
    280
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Yeah I was thinking of getting some T12's too. About how much space do you think is suffiecent for a ventalation gap for my terrarium?
    I regret little to nothing!

    My Growlist

  3. #11
    Veronis's Avatar
    Join Date
    Dec 2007
    Location
    Harrisburg, Pennsylvania
    Posts
    417
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I'd start as close to the terrarium as you can get, set up the fan, and watch the temp/humidity inside the terrarium. Adjust the fan speed and light height as necessary, keeping in mind that the ballasts (the part that gets hot) will 90% of the time be on the same side of the shop light fixture as the power cord.

    Ideally, you want to keep the lights as close to the terrarium as possible so your plants get the most light. Worst case, if you're not putting your soil mix directly into the terrarium (e.g. you're using the tray method with the plant in a pot of its own), you can raise the plant up on a pedestal of some kind (upside down pot, ziploc plastic container, etc.) to get it closer to the light.

    Always measure temp and humidity at the plant level (put the gauge between the top of the plant and its soil).

    Good luck.

  4. #12
    Let's positive thinking! seedjar's Avatar
    Join Date
    Dec 2004
    Location
    Olympia, Washington
    Posts
    4,064
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    I don't like to just flat out contradict people but I must disagree with Valydius on one point - a high CRI is not appropriate for plants. At least, "the highest possible CRI" is an inappropriate criteria. CRI and color temperature are factors having to do with the average color the light puts out. Plants can use light coming from several ranges, so there isn't a single color that you're looking for. (Besides which, "the highest possible" is stuff like UV radiation, X-rays, microwaves...) A lot of growers here report good success with a 50/50 mix of cool and warm white fluorescent bulbs, which are typically rated 6500K and 5000K, respectively. A higher color temperature won't necessarily be better for your plants. (It's also worth noting that, going by reports here and on other growing forums, fluorescent lights sold specifically as "grow bulbs" are no better and often worse than ordinary warm/cool white bulbs.)
    If you really want to find the best light out there, the number you need to optimize on is the photosynthetically active radiation (PAR.) PAR is a measure of the energy in light weighted by its usefulness to plants (so energy in the form of green light, for example, is not included in this measure because plants can't use it for photosynthesis.) Unfortunately, very few bulbs are rated in terms of PAR; the best you'll probably be able to do is to look for independent lab tests and use them as a buying guide. Or, if you know the physics staff at your local university, you may be able to obtain a photospectrometer to do your own research. In any case, the next best thing to look at is lumens, which is a measure similar to PAR but biased towards light visible to humans (note that humans see very different light than plants.) By comparing lumens with respect to electrical consumption (watts) you can get an idea of how much energy the bulb actually sends out as light. Search the forum here for terms like shop lights or PAR and you can find a lot of discussion on the topic. In my experience, four or eight foot shoplights with 40 watt T12-size bulbs are cheapest and most efficient because they're the standard for industrial applications. The rest is a matter of finding good prices and quality bulbs. Remember that fluorescent bulbs lose a lot of power after the first six months of operation, so a cheaper bulb might be worth it the price means you can replace them regularly.
    ~Joe

    PS - Also, when it comes to the CP FAQ, keep in mind that Barry is sometimes kind of a worst-case-scenario type of guy. Modifying your lights is probably not necessary... I don't know a lot of people here that do. I consider my shoplights to be free space heaters, as Washington is a little on the cool side.
    o//~ Livin' like a bug ain't easy / My old clothes don't seem to fit me /
    I got little tiny bug feet / I don't really know what bugs eat /
    Don't want no one steppin' on me / Now I'm sympathizin' with fleas /
    Livin' like a bug ain't easy / Livin' like a bug ain't easy... o//~

  5. #13
    Someday is not a day of the week. Maxx's Avatar
    Join Date
    Aug 2007
    Location
    South-ern California
    Posts
    280
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Okay guys I got a light today. I actually ended up getting a T5 fixture with metal 'dish' , if you will, that spreads out the lighting more.
    I regret little to nothing!

    My Growlist

  6. #14
    D_muscipula's Avatar
    Join Date
    Aug 2007
    Location
    Oregon
    Posts
    1,500
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    go get some four foot shoplights from homedepot for 8-9$
    view my growlist
    http://grwlist.notlong.com

  7. #15
    Hello, I must be going... Not a Number's Avatar
    Join Date
    Nov 2006
    Location
    Los Angeles, CA
    Posts
    7,506
    Mentioned
    5 Post(s)
    Tagged
    0 Thread(s)
    Refer to this thread regarding plant lights:

    http://www.terraforums.com/forums/sh...d.php?t=111643

  8. #16
    Lover of Mountains nightsky's Avatar
    Join Date
    Dec 2007
    Location
    near Salt Lake City
    Posts
    1,409
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I ended up building a plant rack/terrarium driven by the need for light. My apartment just does not get much light, even with a south picture window, due the building next to us blocking out nearly all the sunlight.

    I just bought a couple cheap shoplight ballasts like D muscipula suggested, and put some 40w t12 daylight bulbs in. Stuck them on a timer to come on and off automatically. As a bonus, I can now control my humidity. After just two weeks with this setup, I can already see a difference in my Neps.

    The drawback is temp control is proving challenging.

Page 2 of 3 FirstFirst 123 LastLast

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •