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How to increase the kH in your pond

6th August

The kH is often overlooked but is crucial in the overall health of a successful pond. A low kH, although not obvious initially, can cause serious problems for wildlife in a pond and even lead to fish death. So what is kH and how can this be overcome? Read on to find out more.

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What is kH?What if kH levels are too low?What if kH levels are too high?What are the ideal kH levels?How to test your pond kH levelHow to increase kH levels

What is kH?

KH is the measure of carbonate hardness. Carbonate hardness is the amount of calcium carbonate in your pond. Calcium carbonate is extremely important. It feeds the nitrifying bacteria in your pond that removes the harmful ammonia and nitrates. These bacteria are part of the pond’s biological filter. Moreover, without this bacteria present, the pond health would rely heavily on the mechanical filtration system and therefore is under threat.

What happens if the kH levels get too low?

A low kH in your pond cannot be initially seen. A pond’s pH should lie roughly at the 7.5pH to 8.5pH mark, when harmful ammonia and nitrites enter the pond the kH neutralises it.

The carbonates essentially buffer the water and keep the pH consistent.

What if kH levels are too high?

Subsequently, if there is not enough kH, the harmful ammonia and nitrites start to build up in the pond and cannot be buffered by the kH. Consequently, this causes the pH to rapidly decline and can ultimately lead to a pH crash.

Find out the ideal pond parameters.

What are the ideal kH levels?

KH levels should be around 125ppm but can fluctuate safely by around 20ppm either way.

Although a low kH in your pond cannot be initially seen, you may begin to see your pond deteriorate when the ammonia and nitrite levels begin to rise.

How to test your pond kH level

The best way to test the kH of your pond is by using a pond water pH testing kit. There are many available on the market that will work perfectly.

The test is quick and the results are almost immediate. The colour the test strips turn represents the health of the pond. If your pond pH or kH is low, measures must be put in place quickly to get the pond parameters back to a neutral state.

Related Products

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    Envii Pond Test Strips

    Easy to use Pond Test Strips measuring 5 key water parameters
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  • Front view of Envii Pond Equaliser

    Envii Pond Equaliser

    Stabilises the pH & KH in ponds to keep water safe for fish.
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How to increase kH levels

Baking soda works fine for some uses. Alternatively, we recommend Envii Pond Equaliser to not only raise kH levels but also the pH levels too. Pond Equaliser instantly stabilises the important pond parameters in your pond and buffers the pH, kH and GH for up to 6 months to ensure fish remain safe.

Need help? Get in touch with our friendly customer service team here.

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About the author

Olivia Ball

Marketing Manager

Olivia is our marketing manager, when she’s not planning envii’s next big marketing campaign, coordinating the marketing team or working on reports, you’ll find her spending time with her friends, dancing or working on her next travel plans.

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