Hi. I bought a Fuzion Diablo FP-1000 scale and it read well, then i turned it off and turned it back on for the 2nd time and it read all whack. For example: a gram would be read as 15. So does this mean i need a 1000g weight to calibrate it? this is the exact scale i own: http://www.e-apollo.co.uk/acatalog/Fuzion-FP1000PD.jpg thanks