You need spare tanks Barry. Our son bought us out. I had three of each.
Just got back from town with filled spare tanks of larger capacity.
I can rent the much bigger tanks, but that's about $35 a month now...
Last time I had big tanks, I think my lease on them was about $100 a year.
Guy at the welding supply place informed me we can't legally buy the big tanks anymore. They have to be leased... (Probably just another thing they don't trust us with..)