The single biggest mistake people make is placing live lobsters in a sink or bathtub. If you do this, the lobsters will die immediately.

Salt added to water WILL NOT change this problem.

It is better to keep the lobsters cold in the refrigerator in original bags and covered with a damp cloth. But no more that 24 hours of refrigeration is recommended before cooking live lobster. A basic rule-of-thumb for cooking lobster is "the sooner the better".

 About Eating Saltwater Fish and Lobster Tomalley