In Reply to: LP questions posted by Walt/Tx on November 22, 2017 at 14:51:42:
Local dealers sell propane, 20# and up tanks. Propane is pumped into smaller tank, as you say. They open a vent screw until liquid leaves the tank. I purchase propane in my 100 gallon tank at my house. That has a percentage of fill gauge, that is filled to 80% full, allowing for expansion.
Not sure on the difference between propane and butane. Other more learned minds will answer that one.