One of the features of the house that I purchased is that it has a pond with a small water fall. It is very decorative and I am finding takes a lot of maintence. The first summer I live here I had no clue how to maintain it and keep the alegae down. I am attempting with this to keep a record of what I do to the pond from year to year and hopefully end up with a even better looking pond. The pond measure 76" x 72" x 13" on the main pond and it is not square and to lazy to calculate it completely out. There is a smaller 12" x 12" x 12" pond which the water fall flows from. In total there is about 452.29 gallons of water from what I can gather. The pump that was left for me is a Tetra Pond GP750, which puts out about 750 gallons per minute for up to about 1500 Gallon ponds according to the box.