I caught a 1.5lb Gilthead Bream in the Helford River at Pedn Billy a few years ago! Drive to Helford Passage and leave your car in the car park above the Ferry Boat Inn.
Walk along the road past the Inn and keep going until you reach the beach at the end of the road. Carry on past the boathouse with slipway until you reach a thatched cottage/boathouse. about 1/2 mile walk in all. Fabulous scenery, so walk doesn't seem to take long.
This is Pedn Billy. NOTE that the beach is privately owned (down to the high water mark). So keep below high water mark. I have also caught school bass to 2.5lb, mackeral and red mullet here. Cast 50 to 75 yards out towards boat moorings. Caught bream on cockles I think, but ragworm works well. Tackle shop in Falmouth has good local dug worms usually, not those tiny commercially bred things. You can use light tackle as tide is not fierce. I use a light flattie rod and a Bass rod, with simple running ledger. (Caught a mackeral on a bare hook here when retrieving!!)
I'm sure there must be hot spots in The Helford where bream shoal up, like they do in the Fal. If only had a couple of weeks to explore it thoroughly! Maybe when I retire!
I usually fish 2 hours up and down from high tide. NOTE: Your exit may be cut off at high tide, but as long as you fish over the peak for an hour or two tide will have retreated enough. Apparently it fishes best when the tides are biggest. I rarley blank here, so best of luck. Report back with your huge catch!!
Not sure on the bait/tactics as I don't fish the pool (not a mullet kind of person)
best place for advice is the County Angler Shop in Camborne, a lot of our club members fish the pool (one had a GH last week over 3lb) just drop into the shop or any other tackle shops in the west of the area (Newtown Angling by Praa sands being another one) and they will be only to happy to point you in the right direction.
I think they use float tactics, usual mullet stuff, and fish the pool on the right of the tunnel. hope this helps. Tim
County angler Tel 01209 718490