I'm after some feedback on fluorescent lighting. Actually some
comparisons between normal fluoro tubes, and the cf's that are meant
to replace incandescents.

When I set up my DOTC (done on the cheap) 15 gal planted tank a while
ago, it seemed like a good idea to try out those cf's. A bargain store
chain here in Oz had 24 W daylight (6500K) cf's for Au$8. The
packaging states 1260 lumens for each bulb. So I made up a rain gutter
type hood - except using 150mm PVC cut in half - set a globe in each
end, and was amazed at the brightness and uniform lighting in the
tank.

But after some reading at this group and other places, it seems most
plant people think normal fluoros are better than the cf's. So I went
and bought a twin 20W fixture. It came with cool white tubes, each
stating 1230 lumens. So before buying some better tubes and fitting a
better ballast I have laying around, wired it up, turned it on and was
disgusted at the crap intensity in the tank.

Now, I know the color temperatures between setups is different, and
the cf's have an extra 60 lumens (wow), but I just didn't expect the
huge drop in intensity. So I'm wondering if anyone else has
experienced this. Because from this experiment, I'm thinking of
building a hood for my 4' tank, housing several cf's with the sockets
along the back of the hood so the globes point forwards. This would
also allow a simulated east-to-west sunset, by turning off the globes
one by one.

Any comments on my experience?

Dave