Biological, mechanical, and chemical pond filter media

Keeping your pond water quality stable is crucial in koi keeping, so ensuring you have the best filter media for your pond is important. Whether you’re looking to replace your mechanical filtration or want to increase the biological efficiency of your filter, our range of biological, mechanical and chemical filter media will keep your pond healthy. 

Mechanical filtration

Mechanical filtration, also known as foam filters and filter brushes, is what you add to your pond filter to capture large pieces of detritus in your pond water. Equally, mechanical filtration also provides a level of biological filtration, and can be effective if your pond is unable to hold biological filter media

Biological filtration

Biological filtration is where the nitrogen cycle can be the most effective. Using beads or ceramic media provides a massive surface area, a perfect breeding ground for beneficial bacteria like nitrosomonas and nitrobacter. These bacteria break down toxic ammonia and nitrite, converting them into safer nitrates.

Chemical filtration

Chemical filtration is often in the form of activated carbon, which can be in bags or as foam sheets, and removes potentially harmful chemicals in your water. If you have recently treated your pond and want to ensure your water has none of the chemicals remaining in the pond, you’d add chemical filter media to your filter to absorb them. 

Frequently Asked Questions

How often should I replace my filter media?

We recommend you only replace your filter media once it becomes worn or starts to degrade. If you replace your filter media regularly, your filter will not be as effective as it can be, as the filter media is needed for the nitrogen cycle, which removes harmful ammonia. 

Can I hose my filter media to remove sludge? 

You should not hose your filter media with normal, untreated water. The reason for this is that normal tap water contains chlorine and chloramine, which can remove the beneficial bacteria that help clean your pond water to make it safe for your koi. 

How do you clean filter media? 

To clean your filter media, the best method is to use old pond water. Using a bucket filled with water from your pond, remove the filter media, place it in the bucket and give it a swirl to remove any detritus, like leaves, algae, and sludge. This ensures that the beneficial bacteria remain, but the filter media will become more effective to allow water to pass through. 

Equally, your filter does not need to look clean for it to be effective; if it has small amounts of sludge still on it, this will not stop your filter from working efficiently. 

How long does filter media need to cycle? 

Your filter needs at least 30 days for it to be fully cycled. You will need to add a bacteria source to your pond for your filter to cycle correctly, before adding Koi. We have created a helpful blog that explains how to cycle your filter effectively.