Sea World don't do much for Halloween. They do put up some decorations. If I get time later and figure out how to add pictures I will post some that I took one year.
They also trick or treat on different days. Here are this years dates. October 6,7,13,14,20,21,26,27,28,31, 2007.
They give out some good candy and stuff.
Later,
DisneyScuba