I can certainly relate. I recently had to explain the death of four fish (two neons and two african dwarf frogs) to my son. I am on my way to Petco to argue for a refund. My experience with other fish retailers is that they will be reasonable if you bring in the dead fish and a sample of water. I agree that you should always keep new fish (animals) separated from the rest of your fish for 1-2 weeks to prevent an epidemic. Case in point, a few days after I bought my "sick" fish I returned to Petco for supplies. I noticed that several of the tanks were off limits to the public due to an ick outbreak (including the tank where I got the four departed). I have worked in fish stores and can appreciate how difficult it is to maintain the health of so many tanks, but after I get my refund I will drive the extra few miles to purchase my fish elsewhere.