Natural Ways to Remove Pond Algae

The fish are jumping in the pond, and all seems well. But what is that green substance coating the surface of the pond and hanging in strands off the rushes? It’s algae, a simple plant that is at home in a water environment. Instead of using toxic algae killers, learn natural ways to remove algae and support the pond ecosystem.

Why Algae Blooms in the Pond

An overabundance of algae is called an algal bloom. Algae loves to grow in warm, wet places that are full of nutrients. Any fish pond that gets some sun will have many of the correct conditions for algae to thrive.

Why is Algae Something to Remove from the Pond?

While small amounts of algae are a natural part of the pond environment, a large bloom can indicate that something is out of kilter. Algal blooms can make it hard to see into the water. When algae dies, the decomposition process uses up oxygen, making it harder for water animals to thrive.

Types of Algae

Look into the pond. Are there long strings of green hanging from plants? This is string algae. It can be picked up in chunks. Another sort of algae grows in the water itself, causing it to look muddy or green. This is called plankton.

Spring Cleaning the Pond Helps Avoid and Treat Algae Problems

Winter can be a trying time for a pond. Leaves and branches fall into the water, and the pond is cleaned less frequently. It becomes overloaded with nutrients. If the pond looks very green or is full of stringy algae, consider removing the fish and draining the pond in the spring time. Remove at least half of the water and scrub the pond before reintroducing the animals.

Keep Nutrient Levels Under Control

Work on controlling the level of nutrients that enter the pond. Experiment with how much food the fish actually need. It’s surprising how much fish food actually ends up at the bottom of the pond. Using a pond skimmer, remove debris as it drops into the water.

Add a Pond Filter to Breed Beneficial Bacteria

A healthy population of beneficial bacteria will break down the nutrient-rich sludge that can build up at the bottom of the pond. Removing nutrients controls algae. Add rocks and plants to provide a good environment for these bacteria. Add a filter to the pond as well. Look for a filter than will clean all of the water in the pond every three hours.

While cleaning and scrubbing the pond can be a good thing to do periodically, try not to be overzealous. Frequently adding tap water to the water garden can make it harder for a population of beneficial bacteria to get established.

Aerate the Pond to Control Algae

Algae prefers to grow in quiet water. Moving water pushes the algae through the water body. Add a pond fountain, aerator, waterfall or other water feature to the water garden. This adds oxygen for the fish and moves the water around, making the pond a less than ideal home for algae.

Add Shade to Treat Algae Problems

A shady nook by the pond is a great place to spend a summer’s day. It’s also a less than ideal home for algae, a plant that loves the sunshine. Add water lilies and other floating plants. Surround the pond with shrubs, trees, and reeds. Plants enhance the appearance of the pond and provide valuable shade that controls algae populations.

Tadpoles and Aquatic Insects Remove Algae

Although animal populations are unlikely to remove large quantities of algae, building a pond ecosystem is key to the pond’s overall health. Animals like tadpoles and insect larvae love to eat algae. By providing an environment free of pesticides and rich in reeds and floating plants, animals will come to the pond, make it their home, and become part of the pond food chain.

While a small amount of algae is a normal part of a pond environment, too much can make a pond visually unappealing. It can also lead to depleted oxygen levels in the water garden. Treat the garden pond with thorough cleaning, nutrient control, aeration, filtration, and by introducing shade plants and inviting animals that eat algae.