I sometimes fish that pier in the summer for flatties and it really depends on tide and time of day. Port San Luis is a rather shallow pier with little structure and some growth on the pilings. Perch are found all along the pier but some reliable spots include at the foot where the rocks meet the water. Sharks and rays often frequent the pier using fresh caught smelt or sardos work great but you can get away with frozen bait. If you have the time I would try Cayucus pier it yeilds some better fish and a bigger variety. For halibut I like to catch my own bait small smelt work perfect. Try to always move your bait and try different spots on the pier. Remember to always be experimental, what was working yesterday may not work today. Some salmon are caught every year I like to throw spoons or float live bait on a baloon or large float. Sometimes Mackeral show up and they can be caught on small spoons and spinners , these fish are excellent bait also either cut or live. I hope this makes your next trip a successful one. J