hi all.. stumbled across this website and chart for aquarium ammonia.. so next time before u panic and do lots of things which may screw up your water parameters take a look at this chart and see if your ammonia is really at toxic level or not.. as those test kits that we use measures total ammonia which is ammonia + ammonium and ammonia is the toxic one..
http://www.dataguru.org/misc/aquarium/AmmoniaTox.html