"FDR" wrote in message
...
I don't know about how good they are, but I'd say that fluorescents were
more energy efficient that the sodium lamps.

No, HPS (high pressure sodium) lights produce a lot more light per watt of
electricity used than fluorescent lights. HPS is more efficient than metal
halide too. On the topic of which to choose; if it's just for seedlings
then it won't make much difference, because seedlings don't really need much
light (even fluorescents will do fine). But if you want it for growing
fruit etc indoors during winter, then go for the Sodium light. It's more
efficient than either fluoro or MH, and it gives out the best sprectrum for
blooming. It'll probably cost you more than $20 though, as you'll need a
ballast and fixture as well as the bulb (*DON'T* just put a HPS bulb in an
ordinary light fitting, unless you like bright flashes and white hot glass!
:-p )


OTOH, I wonder how my metal halide lights from my old fish tank would do
with plants.

Yesm metal halide lights will work well, particularly for vegetative growth,
HPS is best for blooming though.
JohnnyJ