It's also good practice to frag off corals that are attached to live rock or at least break the rock down, you would not believe how many crabs and such can make it through dips hiding in rock.

When I get new corals in I dip everything, frag down large rocks unless they are solid, inspect and dip again if needed. Adding H2o2 to my dipping process has helped a lot with micro algae as well as pests that like to hide.

For fish... well I don't mess with wild caught anymore. I try to only purchase aquacultured fish now, seem to have much less problems. Also, aquacultured fish coming from large industry breeders are almost guaranteed to not have real issues like ich...that is until they end up in our systems or stores that don't quarantine. GC REEF is really good about incoming stock and I have always felt comfortable buying fish and coral from them.

I have tried for years to not purchase corals from the wild for the same reasons but I really can't take my eye off scolies and other amazing LPS that aren't good candidates for aquaculture.

When I introduce new fish to my systems (aquaculture only) I like to dose the tank with Marine-Max Water Conditioner (probiotic that helps with disease prevention) and also anytime I do a large water change. I have had great results with this.