Keeping pond water clean and clear can be tricky, but there are pond chemicals, natural treatments and other strategies that can help keep your water as clean as possible. Here’s a quick look at your chemical treatment options.

In order to design the best treatment, it’s important to know which types of algae exist in your pond water. There are three basic categories of algae, including:

Planktonic Algae – If your pond begins to look like pea soup or perhaps bright green in color, this is a sign that planktonic algae have invaded. A small amount of planktonic algae is beneficial, but when it starts to cover 20% of your pond or more, this is too much and you need to bring it under control.

Filamentous Algae – This is the stringy, hairy sort of algae that you probably spend some of your time raking out of your pond. Again, a very small amount of this type of algae can be beneficial, but eventually, it will start to take over the water and oxygen levels will drop, not to mention the unappealing appearance.

If you are dealing with a fairly mild issue of either planktonic or filamentous algae, chemical treatments might not be necessary. The use of beneficial bacteria can remediate these issues and restore pond water. With proper monthly bacteria treatments, you can prevent these issues from occurring again. If you do have a moderate to severe algae issue, pond chemicals such as copper algaecide can be used to mitigate the problem.

Blue-Green Algae – Of all of the types of algae you might encounter, blue-green algae poses the most serious consequences for your pond water. Blue-green algae are toxic, and not just for fish, it also can poison wildlife, livestock and humans. If you notice this type of algae, pond chemicals such as liquid copper algaecide can be used to quickly eliminate this problem.

Keep in mind, copper algaecide cannot be used for ponds with koi fish or trout. Additionally, several states prohibit the use of copper algaecide, so if you live in Alaska, California, Connecticut, Maine, New York, New Jersey or Washington, give us a call and we can discuss other options.

We also highly recommend that you invest in an aeration system, as this also helps keep oxygen levels high and can prevent algal blooms by keeping the water moving and reducing the water temperature.

Weeds – There are also many types of aquatic vegetation that can grow out of control in a pond, including musk grass, cattails, duckweed and more. For more help identifying weeds and types of algae, head to This page will help you identify which weeds or algae are growing in your pond and provide some suggestions for dealing with common pond issues.

Beyond Pond Chemicals
While pond chemicals can be helpful, as stated before, some of these products are not legal for use in certain states such as Alaska, California, Connecticut, Maine, New York, New Jersey and Washington. Even chemicals that are EPA-approved might be illegal for use in your state.

Fortunately, there are many natural products that can be used to improve water clarity and help you enjoy a cleaner pond. Using a product with beneficial bacteria often can reduce or eliminate many pond clarity issues. The bacteria in these natural products will not harm fish, wildlife, livestock or even humans, but it will eat away at the excess nutrients in your pond.

These bacteria are placed into biodegradable or water-soluble containers and you simply toss them into your pond at different locations according to the instructions. The packs last about 30 days, and then you just add new packs into the water.

Monthly treatment with beneficial bacteria can go a long way toward preventing the appearance of green organic material, but if you already are dealing with a murky pond, you might first start by adding a supplement to accelerate the removal of this excess organic material.

Often you will notice that after treatment, your pond water looks a bit worse than it did before. This is simply all of the organic matter coming up from the bottom of the pond to try and find nutrients to feed on. As it dies off, it will float back to the bottom of the pond and the beneficial bacteria will consume the excess nutrients and your water clarity will improve.

In the end, pond chemicals are best suited to treating moderate to severe algae issues but we highly recommend using beneficial bacteria whenever possible, as this can truly improve pond clarity. Treating monthly and adding occasional bacteria supplements is one of the easiest ways to maintain a clean pond.