ask This Old House.

WATER TREATMENT As this newly cleaned pond is being refilled with water, Jenn adds a dose of dechlorinator to ensure that the fish will have a livable habitat when they're reintroduced. When the pond is empty, remove any remaining debris and power-wash the stones that line the pond. • Tips, tricks, and answers to your home-improvement questions How to maintain a pond We have a small man-made pond on our property that fills every year with pine needles and other stuff, creating a very mucky bottom. Lightly sweep off the crumbs of mortar with a stiff -bristled brush, then go back over the joints with a flat brick jointer and smooth the mortar one last time to create a weatherproof surface. [Extracted from the article]