yeah, its cuz AZ is so close to the ocean.
Glad you finally decided. The powder brown, blue and achilles seem to have the same mortality rate. I would try that achilles in my 125 but with a big-a$$ Sohal there in the same family there would be death for sure. I believe the Acanthrus family to be the most aggressive tang.
As for your choice of fish, good luck to you. Get them eating nori asap to keep from HLLE and spirulina for the immune system.
BTW I found out the name of that large coral you asked for, it is a merulina ampliata. pretty cool coral, check one out.
-Doc