I have countless cooks on the 1st tank and it still feels full when just picking it up. I had 2 tanks from my E-310 grill. We just built a new house and I don’t have a shed yet but once my shed is built the second tank can go into storage lol.2 tanks? I will be curious to see how long it takes to empty both of those with a 1200. It may take us 3 or 4 years to find out.