Waiting sounds like the most prudent course to take, I agree. Just for the record what were the other fish types that died? I have had similar episodes in the past were everytime I added another fish to a system that should have been able to handle a new addition easily the fish died within 4-7 days. Finally I decided that there must be some type of spike that I was not seeing and bulked up my biological filter, I have not had that problem since. I am not a huge fan of long drip acclimations for most fish. The fish is already stressed enough and the introduction of O2 to the sealed container causes a pH swing. But everyone does things differently.