I've fished Hardwick a couple of times years ago, just day fishing for tench and had a good net full each time (4lb max). Then the other year I came back for a one off as I had forgotten all about this place and gave it ago for the carp (Mid Feb 2007, very cold & Wet). I blanked but one of the lads fishing there (Johno) had 7 carp out over 24hrs, smallest been 13lb and the biggest been 22lb. (Particles seemed to be the bait of chose).
Not had chance to get back there yet, but hoping to put a full season in next year.