If your new pond has to be built on a budget then it is still possible to use a bottom drain and good standard filtration system. In this example below the pond has been constructed using a butyl liner with only block walls. The base has been simply carved from the soil and has sand and a membrane between the exavation and the liner. Using this simple construction method it is possible to build a pond which is both good for koi and your wallet.
The water feeds the filtration system via a central bottom drain incased in reinforced concrete. The water enters a multibay system which typically contain brushes, japanese matting and large aggregate materials which trap particles and provide the bacteria with a surface upon which to perform the nitrification process. The waste from these chambers are simply purge periodically from the system using valves on the base of each chamber. The clean water is drawn from the filter system by a dry mounted pump, passed through a Ultraviolet clarifier to kill algae cells in the water, and out through a mid or top return to the pond. mavity multibay filter systems work best when the turnover is at least 60% of the pond volume per hour. An advantage is that the pump can be low pressure and low running cost.
