The pond

This is my pond. It's not very big, about 150-200 gallons I think (wild guess) with three pools. The lily pads are native from the ponds of New Hampshire and the bottom is covered with gravel. Water is continually pumped up from the bottom to the top using a small pump which is buried in the gravel of the bottom pool. I don't make any attempt to filter it, but I do change the water regularly, using the old water on the garden and filling up with rain water if I can or dechlorinated tap water if it hasn't rained much (not a problem this summer.) I decided to create a pool because my house is on a granite ledge with naturally occurring crevasses in the rock. Last year I built the walls using regular cement but it leaked horridly (good for the garden) and so this year I coated everything with hydraulic cement which works great. There are about 17 goldfish in the pond, 15 were "rescued" from the feeder tank at Petco and are about a year old now, and 2 are babies which appeared a few weeks ago. Currently three frogs are in residence, one of which wintered over in the pond last year. Various garden snails are in there too and some interesting bugs. No mosquitoes though, because the water is never still ... Rule #1 for healthy urban ponding!