Once there was a green pond that had fish but you couldn’t see them. The pond had a small filter and a pretty waterfall covered by algae. This pond got a present- a brand new wetland filter. The pond owner got an even better present- clean, clear water and happy fish! The fish were so happy they started a family. The End.

Was this a true story? Yes! Last summer (2023), we rehabbed a pond filter system near Medina, MN by installing a wetland filter and the results were dramatic: green, cloudy water turned crystal clear. The pond owners were delighted!

Can a wetland be added to an existing pond?

Yes! This is a great way to give new life to an old pond system. Adding a wetland filter to an existing pond is doable if there is room for it. Just how much room? Well, most of the filter is underground so you don’t even see it. The top of the filter is covered by rock and beautiful aquatic plants. For the engineers among you, below is a chart from Aquascape Inc. showing recommended filter sizes. Please note, if you have a large amount of koi or pond fish, your filter should be upsized to handle the waste.

How does a Wetland Filter work?

A wetland filter removes toxins and nutrients in the water by harnessing Mother Nature’s processes. Sediments have a place to settle out and bacteria safely breaks down nutrients and toxins without harsh pond chemicals.

How much does a wetland cost?

The cost of a wetland depends on two main things:

1. The size needed to properly filter your water and 2. The difficulty of the site. (I.e. do you have room for the filter or do we need to move large stumps out first?!?)

You can expect a price tag of $10-12K for a medium sized pond. Larger, recreational ponds will be higher, of course, but the process is the same and involves excavation of the site, installation of rubber, centipedes, filter blocks, and clean out stations, installation of graduating layers of rock and gravel, installing plants or topdressing the area, and hauling away the fill soil and debris. The new filter would be joined to the existing pond or waterfall and made to look seamless. Its a big, hairy project but the results are long lasting, safe, and clean!

Extra benefits of a wetland filter:

Wetland filters look nice. Generally they look like part of the pond and can have shallow water flowing through them. (picture a babbling brook.)

Wetland filters provide a great spot for beautiful aquatic plants to grow.

The filters don’t have to be drained for winter.

If your pond needs some “happiness added”, summer is the perfect time to repair or upgrade!

For more information on wetland filters, check out the article from Aquascape Inc. or have fun watching these videos!