brndfrb,
I'm not sure if there's a point in time where you think you might be able to upgrade your lighting? Coraline definitely won't spread, or grow under NO lighting, but the coraline is not going to dissapear overnight. We have a bunch of
LR in our refugium that we've pulled out of the display tank, and the refugium has a single Home Depot NO flourescent strip on it. I haven't seen too much of a decline in the coraline in the 5-6 mos. it's been in there.
Lighting is a pain - you're probably looking in the $200.00 - $400.00 range for halfdecent lighting on your tank. That's not including the hood/canopy if you'll need a new one. It all depends on where you want your tank to go eventually - if all you want is
LR, a few '
shrooms, and some polyps, you can probably get away with an IceCap 430 ballast, and 2 36"
VHO bulbs. That would put you at close to 3 watts per gallon. If you're looking to do a full-blown soft coral reef, I'd suggest getting the 660 ballast, and 4 x 36" (95w) bulbs from the outset.
A lot depends on how soon you intend on upgrading. The coraline will survive for some time - 6 mos, 8 mos, possibly a year, though I probably wouldn't attempt to push it that far out.
HTH,