The pond is filled as the liner is put in. This allows us to smooth out some of the wrinkles. When you use a liner you will always have some wrinkles in the liner. As the plants grow (particularly if you have algae!) they will not be very noticeable. Rocks are used to hold the liner. The pump is in the box at the left. The pump circulates the water, pulling it from the pond to the skimmer box.