really no need chumming stripers....they move with the tides. When they are in, they are in. If they are not in, chum won't bring them.
Now some commercial fleets go thru a couple flatts of bait for chumming, but they are tossing small chunks and grinded up fish. They make a thich slick to hold them in place, but again this would be on the ocean front, not often in rivers, channels or bays/flatts.
If you are going to try, herring, mackerel, squid, shrimp, pollock, sand eels are their main forage.