There is also combo tanks, my new CF tank seem to be one of those, in thin metal but wrapped in carbon fiber for strength.
So my new 12 L tank are substantial lighter than my old 12 L steel tank, but not as light as a 100 % carbon fiber bottle,i just dont think you can get 100% carbon bottles in 12 L
My new tank is a Worethington carbondive 300.
http://www.carbondive.com/ Often you buy a bottle with no valve, so just get a valve that is compatible with the charging kit that come with some rifles, or the charging kit you want to use.
As for diving i think there is a couple of main valves, not sure about smoke diving i never really took notice of that getting that education, but i think the valves are the same at least as one of the dive valves ( make little sense to me to have a lot of different valves more or less doing the same job )
Most popular seem to be the M 25 x 2, EN144-1 valves,,,,,,, someone correct me if i am wrong.