From what I've been reading 20 pound with small hook size 4. I was out last month and i killed it with 25 flouro and size 2-1/0 j and circle hooks, the colt snipers(80g) were working really well also flat fall(120g) but i will also be that guy with 6 set ups just in case.
FWIW I was on the Liberty 3/4 day yesterday and it was NOT hard to find fish. Our first stop was not productive so we moved on, second stop (maybe ~9am, I really didn't check) lasted pretty much all day, we were there until 2:00 with a constant steady bite going, 5-6 fish hanging at any given time. School just stayed with us all day and kept playing. ~20lb grade, decent fight on 20. People were fishing 15-25 for the most part, all flylined sardines. I didn't see any fish caught with artificials of any sort. I found it easier to get picked up on 20 than 25 but in some cases it didn't seem to matter, for instance a guy who had straight dark green braid to the hook landed a nice one