The filters in this section are suitable for ponds up to 2,000 gallons. Each filter has a suggested flow rate. Be sure to check the suggested flow rates of each filter. So remember the first rule of sizing a filter for your KOI pond?
"For KOI ponds try to pass a minimum of one pond volume an hour through the filter." This rule applies to KOI ponds. Water gardens with a lot less koi or goldfish can go by another rule. " For Water Gardens try to pass a minimum of one pond volume every two hours through the filter."
Example: If you have a 2000 gallon water garden which is mostly plants and only a few koi then you would only need a filter with a suggested flow rate of 1000 gallons per hour.
On the other hand if your KOI pond is 2000 gallons has lots of hungry koi and the filter you choose can only handle a flow rate of 1000 gallons per hour, you will need 2 of them to get the one pond volume per hour flow through. Every component in your pond system is based on these rules. Once you have determined your pond volume and the fish load then you can properly size your pump, filter and UV clarifier. These components work together and must all match your desired flow rate if you are to be successful.