What type of growlights?
 

I've had a few banana seedlings under fluorescent aquarium growlights this winter. I cant' say growth has been as good as expected.

Would there be a huge difference if you use the natrium greenhouse lights?

Erlend

Re: What type of growlights?
 

Common aquarium bulbs won't produce much intensity in the specturm where photosynthesis occurs.
Since you say that they are 'growlights' designed to grow plants, and that's not doing it much for them, consider getting a ballast thats VHO and a set of endcaps to setup your own 'very high output' grow area. You could also look into a metal halide setup with a common 6500K lamp (better for growing than a 5K or 10K), or even an HPS.

There's a lot of options for you, all depends on the investment you want to make, and the power consumption and heat you want to commit to.

Keep in mind that if the're just seedlings, like you say, you dont want to burn them with too much intensity. Put the bulb high up on the ceiling, and shade them with a screen for the first days and weeks. Monitor them closely the first few hours, though, and keep water around.

Re: What type of growlights?
 

I use Tek-Light T5 high output flouescent, two 8 bulb set ups. They are about $500 a peice, I got mine for free, but they are still really cool and good and you can switch out bulbs really easy depending on what spectrums you want. They dont put out too much heat so you cant burn the plants and they are think and sleek so they fit in small places well. Couple old photos of one of the sets in use. These big ones are about 4ft x 2ft but they come in all kinds of sizes, these are the largest though.

http://i3.photobucket.com/albums/y71...house/high.jpg
http://i3.photobucket.com/albums/y71...se/corner2.jpg