When I go down the garden for the first time in the morning the goldfish congregate by the edge of the pond - feed us, Mum! Any other time they don't bother to come to the surface.
They are self-bred but haven't seen any black ones yet this year. They're the babies and turn gold later on.
The silvery lines are the heron deterrent lines of a commercially available system and it's worked so far in the few years since it was installed. I lost all the goldfish one year and decided to have this system put in. The netting is to stop an inquisitive young cat from across the road from going fishing. I've watched it balancing on the edge to the point of falling in so now the temptation is out of reach - I hope!