Total Failure

[naesco]

All very good advice.
Forget about what your LFS is saying. He makes money selling you fish and reselling them when they die.
In a small tank you should be only adding one fish at a time once a month. The tank adjusts slowly.
If an animal dies you must remove it or is will cause your tank to have an ammonia and than nitrite spike and kill everything.

Do not add any fish to your tank until everything stabilizes and do not add any further chemicals.
Patience is the key in this hobby, eh