I originally did not QT when I had only a nano. That was 3 fish total and just 12 corals. Once I went larger the “stakes” become greater. I actually introduced ich to the nano with that 3rd fish. The close quarters of the tank and the aggression from the clowns caused that 3rd fish to present an ich infection after a month of being introduced. From that point I knew I’d have to be more careful and QT everything when moving to a new larger tank.
CORALS:
I do 76 days for each frag through the coral QT. I also plan to QT CUC in that same tank. I dip in coral RX. I’m likely going to start Bayer dips and possible potassium chloride after @Lexinverts convincing case.
FISH:
For fish, I don’t plan to bring new fish often once I get this initial batch established. I keep ceramic media in my sump in the event I need to start up the QT tank. It’s a 20 tall (width restraint, I wish I could have done a 20 Long) with a hang on back filter, plastic rock structure, and heater. I’m hoping to keep these fish alive for years and years.
My method is based on Marine Collectors and Humblefish:
methylene blue bath
formalin bath
2-3 days of observation and ensure they’re eating, eating is very important
copper power @2.3 ppm for 30 days
formalin bath again
metro in their food for 3 weeks
2 weeks observation
I agree in theory of the philosophy of having healthy fish with strong immune systems. What concerns me is large stress events becoming an outbreak if ich is being “managed” in the tank. A power outrage is my main worry.