Hello everyone...I was gifted two propane tanks one is a 500 gallon the other is a 250 gal.. im planing make a heater for my greenhouse 20x100 which will be placed inside.. also i want to feed hot water under the ground. to warm up my ground. im debating if i should cut the tanks in half and stand them up... or leave them whole... i want a big firebox because i want a good burntime while im away working.. wondering if i should use a water jacket for storage. or use metal pipes in my heat exchanger to warm the water? which will be pumped from the boiler to under ground and returned into a 55 gallon or water jacket just looking for ideas...