I also have a Tank
Tender. You select the tank, push in and hold the button, and then
gently push the plunger until the needle stops rising. Read the indicator (there should be two dials, one for
diesel and one for water) and refer to your table for the level.
Since
tanks are typically such odd shapes, one must come up with your own scale for indicating what the number translates to in terms of gallons or liters.
ID