I house everything as individuals. I am big on keeping track of all my geckos, being housed alone I know if they are eating and pooping regularly. Obviously if they are not then I know which gecko to watch more carefully and so on. Also I think this method is best when breeding because you will never be unsure which female the eggs came from.
i have the females together and males separate i can keep track on my geckos cuz im constently in the tubs, im a small breeder so its easyer for me to keep track