Know the details about your pond before setting out to purchase one. The size of the pond, whether it has plants, fish or both and whether it is in a sunny location all are determining factors. Write down all of the facts and bring them with you so the salesperson knows exactly what you need.
Pick a submerged filter for small- or medium-size ponds and an external filter for a large pond.
Connect the filter to the pump with a hose with threaded connectors.
Tighten the connectors by hand so they will be easy to undo when the pump, hoses or filter needs a cleaning.
Put the hose that exits the filter at the bottom of the pond or attach it to a floating fountain or waterfall.
Place an external filter on a solid, flat surface.
Pick a place in a spot in the pond where a submerged filter is less likely to come in contact with falling leaves and other debris.
Plug the filter into a ground fault circuit interrupter. It will automatically shut down in case of a short circuit.