Fish that you can see can also see you, and that makes them notoriously timid. I find this especially the case with bream in clear shallow water. You need to fish that area at night or when a bit of a chop has stirred the water up a little. If you're bait fishing in a situation like that use unweighted baits on the lightest line and you might get a take. But catching one fish will often scare the others off for half an hour or so, so you might have to move around a bit, but keep your profile low and move slowly to avoid scaring off the fish. Sight fishing can be very rewarding - stalking the fish, putting a bait or lure in just the right place and imparting just enough movement to interest the fish and provoke a strike - it's great stuff, but you have to be very patient and work hard at it. Having a bunch of clowns anywhere near you doesn't help either!
Cheers Freeeedom