I found it here (relevant sections copied below):
Sheepshead is listed in Group 3 of the Snapper/Grouper Management Complex, so the following regulations apply:
B. Season. The season for taking species listed in §A of this regulation is January 1 through December 31.
C. Size Limit. There is no minimum or maximum size limit for the species listed in §A of this regulation.
D. Recreational. An individual may not catch or possess more than:
(3) 20 of any species or any combination of the species listed in §A(3) of this regulation.