i have allways run my refuge 24/7, Helps with the calupra growing stablizing the ph and the adding lights help with keeping the tank heated in the winter
Depends one th calupra you have.. some will go sexual faster than others..
i have grape calupra go over night. then had some never go.. i got alot of razor calupra now, and never an issues with it.. have some in the main tank as well and never goes sexual.