Speci lake used to be ok, had them up to 18lb, fished mainly on the top with dogs or cut down pop up, feed a lot. If you fish the bottom, the bottoms fairly flat at around 6-7ft with a 4ft wide trench going down to 8-9ft all the way around the pool about 10-12 ft out, good for tench there. There are a couple of islands with the depth being around 6ft right up to the bank, method always works well.
Now for the reason i said used to be ok; couple of years ago they ripped all the reeds etc out of the inside margin and totally flatened the banks removing all trees and bushes overhanging the water. Then last year they cut a channel through to an adjacent match pool to create a bigger lake and stocked it full of F1s.
Basically they earn more money from it as a match lake as Heronbrook is one of the largest match complexs around here. all the other lakes( around 7 I think are match waters with carp up to 4-5lb only).
Its not called the Speciman lake any more, I'm not sure what the name is now but if you fish it think of all the F1s you'll have to get through to stand a chance of a decent fish
Have a look;
http://www.heronbrookfisheries.co.uk/
There are still some decent fish in there as seen in the photo gallery, but remember these pics are old, the handsome devil in the hat on page 2 is me and thats about 4 years old.
If your local to the area try Weston Under Lizard AA
http://www.wulac.co.uk/
Hope all this helps
Dave