Need recommendations for lights

[Jorch]

I have been thinking about buying T5's to make my orchids happier. The question is, I don't know how many to buy!

My plants are on a shelf right now, 36" in length, 18" depth, about 18" tall per shelf. The shelf is in front of the south facing patio door, so it does get some light, although not a lot especially over our dark winter. I grow mainly papahs and phrags, with a few oncids and vandas (and misc).

so my questions are:
1) how many T5 tubes do I need per shelf?
2) Should I just buy the 2ft tubes? or spend more and buy a 3ft tube? (I've only seen 3 ft tube offered at one store)

3) I am also thinking of getting a 20 - 30 gallon tank for my miltoniopsis. how many tubes I need for those?

Thanks in advance!! any suggestions are much appreciated!

[Ross]

A couple thoughts: I would start with one fixture for the top shelf and see how it goes. These things tend to be pricey and you don't want to over-buy a size that turns out to be wrong for you. I would not get the 36". It's an odd size and tubes are too rare and expensive. The 48" fixtures are actually shorter than that (I believe something like 46") and the 36" shelf will be right in the center where the light is most consistent and brightest. You don't say how wide your shelves are, but the 4-tube fixture is only 10" wide. So I recommend the 48" 4-tube fixture for the top shelf. My grow window is south-facing and I have 3 compact florescent lights and a 24" fixture in the window to supplement the natural light. Hope this helps.

[let_it_grow]

my set up sounds slot like yours. I started with one bulb and moved to two and will likely get a third and fourth. My Phals have the reddish tint on the leaves so I'm guessing they are getting enough light. I have high and low light plants on different shelves so I'll use 2 bulbs on the low light shelf and 3 or 4 on the higher light shelf. I'm using 2" bulbs but where iget them the price difference between 2, 3 and 4" bulbs is about $1 and all 3 sizes are available at any given point.

[Jorch]

Thanks for your suggestions! I am planning to buy the individual tubes with ballasts and hook them together, so I can add or take away tubes when I need them. The shelf is 18 inches wide, I think it can host a 4 tube unit easily.

My primary concern is my phrags and miltoniopsis. The shelf is only 18 inches high, and the plants themselves are easily over 1 ft tall, so they will be within 5-6 inches of the tube. Will they burn under 4 tubes? I do plan to install at least a fan on each shelf to keep things cooler, although I am not sure how hot the t5 tubes will get.

Thanks again!

[Becca]

I have a 2 ft T5 fixture. Keep in mind they are only about 2000 lumens per bulb, versus the 4 ft bulbs that have a much higher lumens per bulb....almost double if I remember correctly! I regret my 2 ft T5 fixture and wish I had gotten the 4 ft fixture instead, but the 2 ft just seemed to fit better size wise without a ton of over hang. Hope this helps!

[Marty]

You may want to check AHSupply.com for compact fluorescent kits. I got all my vivarium lights from them.