getting back to this.. if you are not entirely happy with the outcome of your complaint, then ask to speak to the manager, or whoever is in charge of the store on the day.
I know from experience that sometimes.. (no matter how terrible it sounds).. just sometimes it is not possible to remove dead fish from a tank immediately because it isnt as simple as getting rid of the fish and chucking it.. mortalities have to be accounted for.. reason for death.. checks on the tank.. water tests...etc etc.. it can be a time consuming process sometimes and usually involves more than one person, just incase someone else has already treated the tank with a chemical that cannot be seen in the tank. it should however be done on a daily basis, and ideally twice a day in the very least (day start / end).
but really if you're a customer in ANY store it is your right in my opinion to be entitled to fair and good service... so if you don't get it, lodge a complaint. no one knows these things occur if it isn't brought to their attention.
I know if someone in the palmy store had a similar complaint, i would personally bring up the nature of the complaint with the manager if i heard of it - even if it is my neck on the line.
it is good to remember that everyone is human and everyone makes mistakes.
To err is human, to forgive is divine. - Alexander Pope.