For light flathead gear I go down to a 1000 reel , 1-3 kg rod , 4 lb line and 8 lb leader , #2 hook on 1-12th oz jig head . I then put on a 2″ soft plastic Berkeley gulp prawn in new penny colour or peppered prawn colour ( green) . These colours are deadly . Another one is the 3″ Berkeley gulp jerk shad in watermelon or light brown . Any lures that are similar will do ok , I just like these ones .Don’t worry about catching some weed , just clear it off and throw out again. The flathead will be there .
If the flats are reasonably sandy with little weed and rock then troll . If the water is running fast then only troll with the current , not against it as the fish will be facing the current . If the current is little or nothing like in Pittwater then troll up and down and in circles as it stirs up the sand and the flathead come and have a look to see if there is any food .
Here I use the normal flathead gear with the soft plastic . Troll at 3 knots max and hold the rod and jig , jig the lure like it is a wounded bait fish , work the tip of the rod jigging so it comes up towards the front of the boat and then drop the rod tip back behind you so the lure drops to the bottom and sits for a second or two . If it is a bit deeper just use the 3/8 jig head .If the lure goes past s flathead it will get nailed .