Fuel tank capacity in 2010 Santa Fe?

We have now taken delivery of our new Santa Fe, and half way through our first tank of gas we're only at about 325 kms - which if you're used to driving a Tahoe is probably spectacular, we are used to cars, and hoping to get at least 600+ kms out of a tank, hopefully 700+.

But I have found a little discrepancy to the actual size of the fuel tank in the vehicle. The owners manual seems to say the tank is only 68L in capacity, whereas the Hyundai Canada website declares it to be 75L, as does the site in the U.S - 19.8 Gal = 75 Litres. So which is it?