Lighting for 2 foot deep tank

I have used standard 48" FL shoplights (4, for a total of 8 x 40 w = 320 
watts of light) on my "optimum" 120 gallon, 2 ft. deep tank for the last 
year.  Plant growth has been generally good, though some plants that 
prefer stronger light (Hygrophila sp., Mexican Oak Leaf) have not done as 
well as I had hoped.

I was particularly encouraged by the growth of E. quadricostatus and 
Anubias nana, which I placed in the relatively dim foreground areas.  
However, E. tenellus has not done as well.  In order to encourage better 
foreground growth, I have recently added three 20 w flourescent spot 
lights aimed at the foreground.  These are 2800k lamps, so while the 
spectrum is not ideal, they do produce a neat simulation of shafts of 
sunlight reaching through to the bottom.  Do they speed up growth?  The 
jury is still out on that...

These fixtures are mounted on a massive hood, which is suspended from the 
ceiling by chains, so that it can be raised and lowered with some 
effort.  I recently refitted two of the fixtures with electronic ballasts 
and T-8 bulbs, which has made the hood noticeably lighter.

So, normal or T-8 flourescents have worked quite well for undemanding 
plants in a 2 foot deep tank, and if you "roll your own" hood, they are 
much cheaper than MHs.

- Jack O'Leary