You are to be commended for being conscientious
However, just relax a bit...
Drip acclimation and quarantine is fine - but don't go hog-wild medicating etc., unless there is a problem.
Observe them in the store - tank raised or wild caught? Tank raised are less likely to have problems. Clownfish usually develop Brooklynella if they're going to develop anything, so ich medication is redundant (in this instance).
If they appear healthy and will eat (ask to see them fed) in the store, take them home and quarantine them. If they don't eat in the store, or don't appear healthy - DON'T BUY THEM.
Quarantine for 2 weeks minimum - if they appear healthy and eat well, then go ahead and move them into the display. If they develop problems during the quarantine time, treat for the specific ailment. Copper won't work on Brooklynella or Trematodes - neither will any of the other common cures out there. Ich remedies won't fix bacterial infections either - treat fish as needed for whatever ailment they are afflicted with - and be careful about mixing medications - interactions can be worse than the illness.
If you take care to select your specimens carefully in the store, you shouldn't have much occasion to medicate.
I wouldn't dip (FW or otherwise) unless you see a problem too - undue stress can do more harm than good.
HTH
Jenn
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Member of the "J" Crowd & the BRW Crowd!
LFS Owner:
Imagine Ocean

Just keep skimming, just keep skimming, just keep skimming, skimming skimming! What do we do? We skim, skim, skim!