Kirk
I guess nobody wants to answer you so here is my response. You're probably wondering why I hadn't responded sooner! For a few days I didn't check the board and I guess your post got lost behind so many others.
My experience is to cull it back to half the area of the sump then spread it out. Harvesting at 2-3 weeks is better than 4-8 weeks. If a lot is taken out at once, other algaes may be able to come in and compete. (this happened to me and started a hair algae bloom) If it is allowed to fill the sump, it cuts out the light and slows growing so that cyanobacteria starts to grow on top(which isn't really all that bad in the short run).
It's also very important to grow a variety of alga other than Caulerpa. I was disappointed to hear that the red stuff you got from me last year had disappeared.
Does anyone have any of the brown sargassum that came in on Fiji LR.
Jon, you are from Fiji, do you have any? I need a small sprig.