It happened while I was moving from my old 33 cube to the new 50. I moved some LR from my nano to the new tank. An hour later I looked at the nano, and it was all green. I looked in the refugium and noted that most of the Caulerpa was transparent. It had sporulated. It was very thick in the refugium. I was able to save only about 10%. Interestingly I gave away a ton of it the day before, because I shut my 10 gallon refugium down.
I put some photos here;
http://www.pbase.com/rcipema/newtank , as I still have to set up FTP with my new hosting company.