Don't give up mate, the feeling of getting a fish that's been so difficult makes it worth carrying on trying! Here is a spot my friend had one at last night, its the second one of these that I saw come from this area yesterday. 99:111 middle of the beach bit casting over to the dead tree branches bit laying in the water and that area. I haven't got one yet but maybe it will be lucky for you, \o There are other areas all over that I've been told about but this one looks the best yet.
P.s funny JHendrix mentioned golden tench, as that's next on my hit list after this species lol.