You need to work out where you think the mullet will be feeding. Where would they be expecting to find nutrient rich mud, algae covered rocks, seaweed?
Look for holding areas, around piers and jetties, back eddies along the river, deeper pools amongst the drowned sand dunes. The good news is that, if you are putting in plenty of loose-feed, in the right place, they will come to feed on it. So throwing spoon-fulls of bread mash will have them feeding near the surface, and a bread-bag will attract them from the depths to feed from the mesh.
