I'm not sure about the docks , but I see and catch more around weed beds. The scuds hang out in the weeds in a particular reservoir where I fish and that seems to be the main diet for them.
I've fished the sandy bottoms there and don't see nearly as many trout. If there are crayfish roaming around you may get into them, but I still would find some weed beds or or a creek inlet,
or some drop offs to locate them. Where I fish, tip-ups probably wouldn't work too well for the larger trout. They tend to go by feel a lot and will spit it out if its not right. Good luck.
