A pond is supposed to have that fresh-looking appeal. Because of algae, however, a once beautiful pond might become an unsightly, not to mention unhealthy, body of water. There are products that you can use to kill algae, but because they can also potentially kill the fish and plants in the pond, it is much better to go the natural way. Here are some ways to prevent algae from growing in the pond without the use of chemicals.
- Understand how algae grows. Knowing the biology of algae will help you understand better how to kill algae. Algae primarily feed on the nutrients present in the pond, which can come from the plants and fish. So when there is a high level of nutrients in the water, algae are much more likely to grow. Your goal, therefore, is mainly to decrease the nutrition level in the pond.
- Put more floating plants. Because these floating plants—which include water lettuce and hyacinth—heavily feed on nutrients, there will be fewer nutrients left for algae. And this will eventually thwart algae growth. Experts say that around 70% of the water should be covered with such plants. Not only will this percentage decrease the nutrients, but this can also block sunlight. Too much sun, especially during summer, can promote algae growth.
- Install shading. Other than floating plants in the pond, you can also use other forms of shade. Examples are sail shades and Styrofoam. You can also try to use water colorants. These colorants, which often come in black and blue, block sunlight and therefore prevent the growth of algae.
- Limit the fish number in the pond. The fewer the fishes, the lower the nutrient level will be. And this translates to less algae growth. Experts also advise not to overfeed the fish. If there’s algae in the pond, it is advised to remove some of the fishes and reduce fish feeds.
- Address water runoff. Make sure the pond is completely protected from water runoff. Specifically, water runoff from the garden may contain fertilizers that can sustain algae life. To avoid this, consider installing berm that will prevent water from running into the pond.
- Change the pond water. Because stagnant water promotes algae growth, it is very important to change the pond water regularly. This especially applies during summer and spring when algae growth is very likely. Replace 1/3 of the water wit fresh water, but make sure to dechlorinate if you are using chlorinated fresh water.
- Use UV clarifier. A UV clarifier will remove algae from the pond. It is available in pond supply stores. If you prefer, use the UV clarifier with a biological filter. A biological filter will eliminate any impurities from the water.
- Get rid of the debris. Any debris that floats to the surface or settles down below should be removed. This includes plant trimmings, dead leaves, and branches, which contain nutrients that can sustain algae growth.
Remember to immediately remove algae from the pond. You can do this by manually raking the algae off. This can be a tedious process but can ultimately benefit your pond in the long run.