New guy with a question about the feldon calculator

[1961shasta]

If I am using a 40 pound propane tank, when using the Feldon calculator do I use the box marked "cylinder type cooking chamber" or "tank Cooking chamber" this may sound dumb but a tank can be round or oblong. not sure what they call a "tank". I do realize propane comes in a "tank", and many are used for smoking so I would assume that is what that are calling a tank. Right?

 

[daveomak]

Look at this tutorial....

http://www.smokingmeatforums.com/a/reverse-flow-smoker-how-to-calculate-build-tutorial