Used too fish it regularly as a kid and went back after a 30 year gap last August..
It was not nearly as well kept or as deep as I remembered, but as we were staying with friends in the area so I thought I would give it a try one afternoon. Had lots of small (and I mean small) roach on float fished maggot and a switch to bread flake produced a small carp that looked to be about a pound. A bloke walking his dog stopped for a chat who said he fished it fairly regularly and there were tench and bigger carp in there but early morning or late evening was the best time. He said you were supposed to have a permit from Croydon Council to fish it, but he claimed that no one ever came around to check.
The only other people fishing that day were a large group of West Indians who had set up a barbie with accompanying music and plenty of beer. Dont know if they caught much but they invited me to join them and I spent a very pleasant few hours.