[thegumbos]

Ron & Terrie: thanks for all the info! It's really helpful. But I'm still confused. If my rig's stated capacity is 64 gallons, and, if I subtract 12 gallons for the hot water heater and, let's say 2 gallons for lines, etc., I should then have at least 50 gallons in the tank. If, as you say, the tank is sloped to get the most out of the tank when level, shouldn't I measure close to 50 gallons when I drain the tank (not 43 gallons)?