Lighting for 125g tank

Tom wrote;

I am in the process of setting up 125 gallon plant tank.  It is 72 inches
long, 18 inches wide, & 20 inches tall.  I was thinking of using 8 standard
T8 bulbs staggared which would give me a little over 2 Watts per gallon.
Would it be more cost effective in the long run to use a 250W metal halide
setup?  Would one MH bulb provide enough light to cover the entire length of
the tank.  What kind of lighting configuration do most people use with this
size tank?  I am open to any and all suggestions.


I have a 150 gallon tank currently configured for live plants.  I use a MH lighting system.  At first I tried using a single bulb as high as 400W and though the lighting intensity was more than adequate the coverage was unacceptable.  In the end I came to two conclusions.  First, I would need two bulbs in order to evenly distribute light accross such a large area.  Second, I would have to construct my own system (especially the canopy) in order to acheive the light distribution I was looking for while maintaining some sense of aesthetic appeal.  In the end I built a remote ballast system with two 250 W MH bulbs and have been extreamly happy with their performance and the response of my plants.

Scott Corbeil