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Enough light for plants == too much for Cardinal tetras?

Hi all,

I'm looking for advice from folks who have kept Cardinal Tetras in planted
tanks...  My 29-gallon (U.S.) tank has been set up for about 3 months now
and is growing great!  Over the last week I've added 14 Cardinal tetras to
the setup, and they look beautiful against all the green.

When the fluorescent lights go on in the morning (Four 20-Watt 24-inch tubes), 
the tetras immediately sink down into the foliage and the back corners of 
the tank.  While the lights are on, they spend all of their time schooling 
back and forth at the very back of the tank (where a black cloth is draped 
for background color).  When the lights go off in the evening, they seem 
to relax, stop schooling as much, and go meandering all over the tank.

Now, most fish books I've read do say that Cardinals like low light levels.
What I'd like to hear from you folks is whether being "confined" to the
back 3-4 inches of the tank during the day is stressful for them.  Should
I try to create more shaded areas for them to spend the day in?  (This 
would be hard as most of my plants love the bright light.)  It's already
heavily planted, but during the day the fish don't venture into the
really overgrown plant thickets except along the back wall.

Is it possible to acclimate Cardinals to brighter lights than they're 
used to?  If they avoid bright lights because it hurts their eyes, probably
not, but maybe they just like the dark to avoid being seen by predators?
Does anyone here keep Cardinals who are comfortable swimming in the direct
light of about 3 Watts/gallon?  

My other thought was, maybe I could use a higher proportion of those
"grow-lux" bulbs that emit more reddish wavelengths and look dimmer to 
the human eye.  Do they look dimmer to fish, too?  How about plants?

Or should I just shut up and enjoy watching my fish?  :)

I'd appreciate any thoughts you experts out there might have.  Thanks!