I want to remove an existing fish pond and fill it in so that the space can be used for normal landscaping in my back yard. The pond is approximately 18 ' long and the widest area is approximately 8' wide. The pond is about 3'deep at the widest area and approximately 2 1/2' deep at the other end. Approximately 2000 gallons, shaped sort of like a foot print. How do I fill it in with dirt. Gravel, rocks? Thanks.