Depending on where you live, be very careful about filling an oil tank with Kerosene. It has happened that people with full tanks living in an isolated area find their tanks emptied maliciously - and not only this, the damage caused by Kerosene leaks can cause major damage to house foundations, gardens etc. I've also heard that this has happened in small estates in the rural areas in the country. Apparently the 'uninvited guests' now don't bother trying to siphon the oil through the normal fittings on the tank - they just cut the pipe and take as much as they can, resulting in the leaks.