KW, Admittedly I have NO science, experience or knowledge in this realm, so with that being said, If you are not in a hurry, I dont think staying at 13/11 will cause any issues, just take a little longer. They love light..haha, however if under time constraints, could drop to 12/12, maybe even 12.5/11.5 for a few days then 12/12 as that would mimic nature a little more and minimize stress (if that could even be a stresser?). I look forward to others answers on this as well..