Dave - its really hard to say you know? There are so many moving parts to this animal. If you get you phospates low..but cant balance the Ph then it all goes awry anyway..etc.
However - I am a great beliver in more biology-less technolgy, as Dave Bornemen says. So a refugium makes perfect sense to me..and its real easy to get it going. I have noticed the algae doesnt grow like it used to in the main tank, before i installed the fuge. It still does, but I have an overstocked tank - so I deal with my issues (fish keep getting bigger wife, or maybe me, loves too much to let them go).
Its also a great place to keep shrimps, crabs, inverts and pods..and all kinds of other things that the hungry fish would love to snack on. Mine is ahead of my skimmer and filter sock..so any detritus goes right to the fuge. I use an old 10 gal with an ovverflow into my sump, and routed the overflow from the tank to the fuge instead of direct to the sump...it was an easy install. Not ideal, as some folks have other ways of routing, but it worked for me.
Just use an incandescent bulb - easy and cheap grows macro like crazy -great dinner garden! heh heh