Crystal-clear water for koi - fish ponds for gardens - Brief Article

Sunset, July, 2001 by Lauren Bonar Swezey

* A gorgeous pond filled with colorful fish can add serenity to a garden. But keeping it clean and free of algae takes careful planning. Sharon and Fred Andres of Saratoga, California, found the ideal solution for keeping their pond--A feet deep, 20 feet wide, and 32 feet long--crystal clear and their 40 koi healthy: a biological filtering tank (see drawing below).

The tank, hidden from view by foliage and a pavilion, has a side trough that traps heavy debris such as fallen leaves; gravel filters out smaller particles. The trough needs cleaning only four times a year, which takes about 5 minutes. Filtered water is recirculated from the tank to the pond by a hidden 3/4-horsepower pump.