It depends on what kind of fish you want to eat. Personally, I feel that the best place to cook boiled fish and spicy fish is in Shennongjia, 30 meters west of the big locust tree on Liuzhuang Street. If it's a turtle. Needless to say, it’s worth a thousand pieces of gold. There is also a small shop on the west side of Tsinghua Park (opposite the old Malian troops) that specializes in soft-shelled turtles and chickens. Very well done too. I forgot the name of the store, I'll know it just by asking.