So I recently just had a major die off..as in all but 3 fish in my tank....all my water levels were fine..although the ammonia is on the high side..but it always has been. Even water that I tested directly from the tap shows high ammonia. Can that be correct? Isn't ammonia in tap water BAD? I got some ammonia blocker that was supposed to bind to and neutralize ammonia..I put the recommended amount in my tank and nothing..figured since everything was dead anyway I'd add more..put 1, then 2 doses more in..still nothing..does this make sense?