Artificial, that way its also not as hard on the female. If you let her incubate them she will not eat until the eggs have hatched and her tub cleaned really good. She will go off feed during breeding, but will stay off food for longer if you let her incubate them. Once eggs are laid and taken away. Most of my females start eating again within a week 3 to 5 days. If eggs are taken away and tubs, female are washed really good. If not you can add about 60 days to you female not eating. Give or take a few days. Its always good to get them eating again soon as you can.