Are you looking at one to buy? If so, that should be one of your points of inspection. I looked at mine when I bought it and the tank capacity was stamped on the tank certification by the manufacturer.
John, No already have the boat..... long story. The label on the sette tank is unreadable, and I dont want to take up the floorboards for the bilge tank. I am going to use the numbers from the 38. capasity is with in 1 gallon or 2.