How To Clean Algae Off Of Pond Rocks (Step by Step Guide)

Having algae in your pond is a natural occurrence that most people with a pond will have to deal with at some point.

This article will provide you with a step-by-step guide to the best ways to clean the algae off the rocks in your pond. There are a variety of different methods and treatments that you can use to ensure that you have a healthy, clean pond.

If you follow the steps below and use the treatments that are recommended then you should find you have a healthy, easy to maintain pond in your garden.

Step 1 – Clean the rocks

The first step in having a pond clear of algae is to clean the rocks or boulders in your pond. You can do this using one of two methods. You can either use a pressure washer or clean the rocks by hand using a firm scrubbing brush.

Pressure Washer

The first way that you can clean the algae off the rocks in your pond is by using a pressure washer. Start by draining your pond of its water as this gives you better access to the rocks. Then use the pressure washer on all the rocks that are affected by the algae.

As pressure washers are very powerful, this is a quick and easy way to clean the rocks covered in algae. This will also help to remove any grime or scum at the bottom of the pond that you would not normally see.

However, if you are deciding to clean the algae from your rocks using a pressure washer, you may need to invest in a pond skimmer.

Pond skimmers remove floating debris and dead plant matter off the surface of a pond before it has a chance to fall to the bottom.

Once you refill your pond after pressure washing, you may find any debris or scum you have missed sit on top of the surface for a little while, hence a pond skimmer would come in handy. Alternatively, you could remove the debris by using a rake or fishing net.

Another way of using your pressure washer to clean the algae off your rocks is to remove all the affected rocks and stone from your pond and lay them in your garden. You would then use the pressure washer to clean the rocks individually.

If you choose to use this method then you need to take extra care of your garden as it can cause damage. Pressure washing is however a great method to ensure you have completely removed the algae. You should also dry the rocks before placing them back in your pond.

Using a firm scrubbing brush

Another method of cleaning the algae from your pond instead of a pressure washer is by using a firm brush. Without a doubt using a pressure washer will be the fastest and most effective way of cleaning your stones but this is not always an option and some of your rocks may be easily damaged. Therefore, using a brush may be better for certain rocks.

The best way to do this is to drain the pond of the water and scrub the algae off the rocks using the brush. Although it is easier to remove the algae if the rocks are still wet, so we advise that you leave a small amount of water at the bottom of pond to make them easier to clean.

Step 2 – Post-treatment filter cleaning

Once you have cleaned the algae from your pond rocks, you need to ensure you clean or replace the pump filter afterwards. It does not matter which method you chose to use to clean your pond rocks, this is always the next recommended step.

If you do not regularly change the filter on your pump, this can lead to further rapid algae growth meaning you will have to clear out your pond more frequently. Having a new filter can stop the algae building up but it can also remove debris and scum from your pond that you may have missed when cleaning.

When cleaning your filter out it is not recommended that you use your pressure washer as this can cause damage, but instead use a garden hose as this is a lot less powerful. If you were to use a pressure washer, this can mess with the insides of your filter.

Step 3 – Understand the ecosystem of your pond

To prevent algae growth, it is important to understand the ecosystem of your pond. To understand the ecosystem of your pond you need to understand the pH levels of the pond and how the organism’s work.

The best way to test the pH balance in your pond is to buy a water testing kit which can test for a variety of things in your pond. These can include testing for pH, ammonia, nitrates, and phosphates, which can all be detrimental to your pond and fish if not regularly checked.

If not checked regularly then these minerals in your pond can speed up the growth of algae. Also, by adding plants into your pond can help to reduce the level of algae in your pond. This is because the plants can act as shade for the pond which helps to ‘starve’ the algae. If there is less algae in your pond, then you will not have to spend hours scrubbing and cleaning the rocks as often.

Step 4 – Prevent algae from building up in your pond

The last step is making sure that you take precautions to prevent the algae from building up in your pond after cleaning it out. One of the easiest ways to do this is to make sure your pond water is moving at all times. This will stop the water from turning stagnant – which algae thrives in. By keeping it moving you will also keep the water filtering through the pump which allows the water to remain clear.

Having a filter in your pond can have great benefits and helps to constantly cycle the water. With a still pond you may tend to find your water going green and this in turn can make it smell. You can add treatments into the water to maintain the pH levels if you wanted to use a chemical solution.

Having a natural and clear pond can be easy if you follow the right steps. You can for example add plants and ensure you have the correct balance of chemicals and minerals. This can act as a natural prevention for algae to stop it building up in your pond and on your rocks.

Conclusion

To conclude, if you follow this step-by-step guide you should find that your pond rocks are free from algae. 

In essence, to clean the algae from your pond there are two simple ways. You can either use a pressure washer or scrub the rocks by hand. The pressure washer will of course be quicker but if you clean the rocks by hand, this is better for the more delicate rocks.

You should also ensure that you replace or change your filter regularly. This can help you to easily maintain the cleanliness of your pond to prevent excessive algae build-up. Also, it is highly important that you constantly monitor the levels in your pond as this could be helping your algae to grow at a faster rate.