I had 13. I started with one nice dem, and ordered 12 more online. the 12 were a little smaller than the first one which became the alpha male. Everything was perfect, he kept all the others in line. I came home to find my alpha male had got his head stuck in a weird opening on my texas holey rock. after that, the dems went to war to find a new alpha. 2 dems died from the stress. so, I'm down to 10. I'd like to get a few more as 12-15 is the best ratio for them, but theres a tenative peace right now and i dont want to disturb it. oh, and I took the piece of holey rock out and broke off the piece that had that opening. they use the overhang as a little cave now, lol.
As far as the camera, it was a nikon. i think a d90. Im not sure. it was expensive though. my sis takes tons of cool photos. When I was taking the shots, it took some patience, but i ended up with some good ones. my main tank is very active and they follow me everywhere. the other one with the mbamba is the opposite. if they see the food, they will stay out, but otherwise they hide when they see people. much harder to get them