My guy has been under now for 4 weeks. Any idea how much longer they usually take? He is just a bit bigger than a quarter...at least his shell is. I'm starting to get nervous, but trying not to be ... only because a little guy I had went under and after 10 weeks I found out he was dead! He was probably suffering PPS though, where I don't think this one is. He was with me a while before going under.