Fork lift tanks are designed to draw LIQUID LP gas not vapor! That's why they are mounted horiziantly. If you are concerned about the available amount of fuel gas you could go to a 40 lb LP vapor tank thats sits verticaly, it is still light enough to be carried easily. LP tanks should never be used (or stored) in any residence, including a garage attached to a residence. Set the tank outside and run the hose under the garage door. I have seen the results of 2 LP gas explosions, it ain't pretty. Unlike natural gas, which is lighter than air LP is heavier than air, so it will flow along the lowest level like water and WILL reach a source of ignition. By putting the tank in an unconfined area, like outdoors, you can reduce the chances of fuel/air/ignition mixture. LP gas is at least as dangerous as gasoline, mostly because, unlike natural gas, it's available in portable containers.