10-15 lbs main with 10-15lbs leader
The bay Snapper are easily spooked and sometimes 10 lbs leader is needed.
I like Sunline Super PE, 12 or 15 lbs will do and you should fit the 300m spool on a 4000fb, this will also be good enough to tackle a LT Tuna or mack that often show up while Snapper fishing