, I think the key to the success of a refugium is variety. I have chaeto, I have three types of caulerpa, I have gracillaria. Yes, I am pruning the fuge on a weekly basis. My lights are kept on 24/7, they are NO flourescents, stuff grows like mad.My lights are right on top of the fuge. I also grow the prolifera in several other tanks. It has gone sexual once, due to my neglect. If you pay any attention at all to what is going on in your tank, you will not have any problems seeing the
signs that give warning to the event. Chaeto, from all that I have read, just does not export nutrients to the extent that those of us with overfed fat fish, need.
One point on the pruning of caulerpa, do not cut it. PINCH it off ...hold the pinch a few seconds than finish pinching the branches off.