Sorry I did not know this was going into a housing discussion, so I will explain.

The male came from the same petstore last week, (housed in groups of pairs or all females) and I suspect same breeder based on time they all came in. So I decided to quarantine them together in a 2'x2'x1' tank together with ample hiding, heat/cool and perch area, at least while young. I have administered many medications in the past over the last 30 years, so feel comfortable in this aspect of the husbandry. I would be more careful if I start buying more carpets, from private breeders who's snakes have not found themselves in the pet store chain.

From reading threads (comments of those who have large collections) and discussing with a couple breeders, no one has ever witnessed an issue with pairs or all females if kept close to the same size. The only issue I have heard being of concern is at feeding time, and I plan to spend more time understanding if that is going to be the deal breaker in housing them together. Also I will investigate if she could breed too early under these conditions. That seems to be another valid concern.

To the point of: To this point everything seems wrong here. A young male coastal "hiding away" which leads me to believe that snake is rather new as well and possibly nervous and unsettled.

It was in the evening that I introduced the female and the male had not come out of his hide yet. Not sure what is weird about that. He hides in the day and comes out on his perch at night. I think if you provide an appropriate hide for a Carpet Python, you will see they use it too. For example, not a big open hide box for zero since of security. I have a hide that he can squeeze into and feel protection on top/bottom. Actually, they are both using this hide now (it is more of a crevice than a hide) and I suspect they will both be on the perch tonight. I have a similar hide on the warm side, but since it is warm right now in Southern California, they prefer the cool hide.