Re: What lights to buy?

>I am under the impression 
>that a 5000K fluorescent bulb is a 5000K fluorescent bulb; is that correct?
Not necessarily.  The Color Temperature of a lamp doesn't tell you anything
about the lamps spectral distribution.  It simply tells you what the output of
the lamp _looks_ like.  A 5000K lamp could have a single peak at 5000K or it
could be a full spectrum lamp with a very uniform spectral distribution, which
on average, looks like 5000K.  The only way to know for sure is to the the
lamps output spectrum.

As for what size and how many lamps the ballast will run, that depends on the
ballast.  Ask to see the manufacturers specs/wiring diagrams.