Pond Filter Size Recommender

Filters are rated differently depending on how heavily stocked your pond is — an ornamental pond with few fish needs far less filtration than the same size pond with a full stock of koi or goldfish. Enter your pond volume and stocking level below to see real filters from our filter range rated for it.

Frequently Asked Questions

Why does stocking level change the filter recommendation?

Fish waste is the main source of the nutrients a filter has to process. A heavily stocked or koi pond produces far more waste per litre than an ornamental pond with few or no fish, so it needs a larger filter rated for that heavier bioload at the same water volume.

Should I size up if I plan to add more fish later?

Yes — it's generally worth sizing a filter for the stocking level you expect to reach eventually, not just your current fish count, since filtration capacity is much easier to plan for upfront than to upgrade later.