weight of dive tank empty
a typical steel 30 pound liquid propane tank weighs about 25-28 pounds empty. propane tank markings (on collar) propane weighs about 4.125 pounds per gallon and a 30 poâ¦und tank will hold about 7.5 gallons so a full tank will weigh about 55 pounds or so. It depends on the size of the tank. The standard tank used at most scuba diving training facilities use an aluminum 80. The tank weighs around 21 lbs. full. As the tank is useâ¦d during diving it becomes more boyant, meaning that you need to use more weight at the end of the dive then you need at the beginning.