Bought my 9 yr old a 3 gal. fish tank has a cool filtering system - different from when I was a kid and had fish. Anyway we ran it for 24 hours like instructed, the man from the pet sotre had me add Aqua Safe to the tank. We added fish 24 hours later like he said. One fish and the algae eater died. So I went back to the store three days later and the girl sold me live bacteria (stress zyme) and instructed me to add to the tank and do this once a week for three weeks. So far I have only added one dose and the whole tank smells including my son's room. Is this normal? The smell is really bad, although so far the other fish seem okay.

Thank you.