We were told our Maroon would host a green BTA, but it's been in the tank for a couple weeks now and still the maroon has not touched it. Is this typical? I hear it's hit or miss with the whole "hosting" thing.
Yep its hit or miss, some will some wont, some take 30 seconds to recognize their host, some take a year or more. Wild caught species tend to host quickly while aquacultured seem to take longer and tank raised IMO are the most difficult.