Question about lighting a terrarium

[ChrisAZ]

Hello, I am a new member to this site looking for some guidance from some experienced members. I am in the process of building a glass terrarium measuring 45" tall by 30" wide by 20" deep. I am lining the walls with Epiweb and I am planning on lighting the enclosure with 2 ft. T5 fluorescent lights plus 1 or 2 small spotlights. My question is, would a 4 bulb T5 fixture be sufficient or should I order the 6 bulb fixture? Is there any sort of formula for lighting? I'm also looking for any experienced members with terrariums this size that would be willing to offer some guidance. I have a lot of questions. Thank you.

[Connie Star]

I don't grow in terrariums but I do grow a lot under lights, T5s primarily. There are some excellent resources on the color temperatures of the lights to use.
One of the OB members Ray Barkalow of First Rays has made some wonderful information available at First Rays' Free Info. He has several things on artificial lights. I would get the 4, not the 6 tube set-up with 2 3200 and 2 5600 lamps. Ray also sells these for good prices. I have bought a number of things from Ray. And I don't get any discounts for singing his praises. Good luck

[ChrisAZ]

Thanks Connie. I found some useful info on Ray's site. Can I ask why you recommend 4 over 6 bulbs? Would six be too bright?

[Connie Star]

It's not a matter of brightness- from you description of your set-up, I think the 6 light fixtures would be too wide for your terrarium. You can check the dimensions of the fixture and match them up.
I've rigged up some shelves with "fixtures" that I made using daisy chained single T5 fixtures attached to steel shelves with zip ties and aluminum foil for a reflector.
http://www.orchidboard.com/community...-email5135.jpg
http://www.orchidboard.com/community...-email5127.jpg
You can probably tell from the bird feeder ropes in the window that my hubby and I do a lot of improvising.
This might not work so well over a terrarium but it does save some money. Let me know if you can't see the photos.

[Magnus A]

The problem will not be to much light with a 6 tube setup but a heat problem. If you do not need to care about heat more light is always better.

The spectra of T5-bulbs do not contain UV-light to burn orchids. Though some heat radiation and alot of heat conduction to cook your orchids in the growing cabinet.

[DelawareJim]

Karma in Sweden has a fairly extensive blog on building and maintaining her orchidarium. Don't remember the details on the exact dimensions, but her blog is here: Orchid Karma

As Magnus said, heat will be your biggest issue.

Cheers.
Jim

[ChrisAZ]

Thank you Jim. I've been reading Karma's blog, it's very helpfull!

---------- Post added at 04:21 PM ---------- Previous post was at 04:08 PM ----------

Thank you everyone for the great feedback so far!
Can anyone tell me if there would be a better option for lighting this terrarium. Once again the dimensions are 45"tall x 30"wide x 20"deep. I was planning on using a 2' 4 lamp T5 fixture, however I'm open to any suggestions. Of course I want as much light as possible to reach the whole terrarium with as little heat as possible.

It depends on what kind of orchids you will be growing and if your plants are going to be standing at the bottom of your terrarium or you will raise them on shelves.
For example for phalaenopsis orchids 4 tubes of T5 HO fixture at about 2ft from the tallest leaves would work good. Cattleyas and vandas would need to be much closer to the lights.

[ChrisAZ]

I realize I've been vague about what I'm doing with this enclosure. This will be a naturalistic display terrarium. The walls as well as lots of branches will be covered with small orchid species, ferns, moss, and other tropicals. I have been searching this and other forums collecting as much info as I can on similar builds. Based on the info I've found so far it sounds like LEDs or a combination of LEDs and T5s would be best. Can anyone recommend an ideal light set up for this build? I don't have any experience with LEDs.