In CA, DUI's qualify for expungement, but the court is getting much tighter in granting them for DUI related offenses.
You are not able to seal a DUI in the state of Florida. Since you were convicted (as is mandatory in DUI cases) you are unable to get this charge sealed.
I agree with the other responses. A Florida DUI is not eligible for sealing. You can only expunge a charge that has been declined by the State. Check out FDLE'S website for a list of offenses that are not eligible for sealing or expunging.