What causes algae to grow in your pond? Algae essentially requires light, nutrients (nitrogen and phosphates), carbon dioxide and ideal water conditions in order to grow. By managing these elements, you will be able to manage your algae growth. There are two basic approaches to managing algae; reactive - when you have a problem that you need to address right away and preventative – when you manage elements in your pond before you have a problem so that algae doesn’t get out of control. We will discuss reactive management techniques here and proctive treatment in “Stopping algae before it starts” on page 6.
There are also two main types of algae; planktonic and string algae. Planktonic algae is a single celled algae and is suspended in the water. During a bloom it can look like a coating on the surface or make the water difficult to see through but it is too small to be removed with nets. Planktonic algae often grows in calm water which allows it to move up and down from the water surface. Be careful not confuse this with cyanobacteria (“blue-green algae”) or floating leaf plants, like duckweed and watermeal, that we will address in the “Duckweed & Watermeal” section on page 12. The other type of algae is string algae which generally grows in mats and looks like green, yellow or brown hair. This algae is often seen in streams or waterfalls where there is lots of water moving past it. It can also grow on the bottom of the pond and then float to the surface in clumps or mats if there is a lot of nutrient available.
Reactive management generally centers around products that eliminate the algae in the short term, like algaecides, but do not address the cause of the algae. This approach is generally used when there is a sudden bloom or the owner is having an event such as a party or wedding and the pond needs to be cleaned up right away. The other reactive product line that can be very effective for quick solutions are nutrient binders that tie up the food source the algae is thriving on.
Products that kill algae are called algaecides, such as Pond Wizard Algaecide. These products are regulated by the government and can be used with a permit in enclosed ponds and lakes only. We can discuss the process to gain access to these products, just send us an email or call. Many algaecides are copper based, which means they are not safe for any fish in the carp family like goldfish or koi so they should not be used if you have these species of fish.
Another option that can be effective more rapidly, especially with planktonic algae are nutrient binders and flocculants. Binding phosphorus specifically removes an important food source for algae and by removing it you can interrupt the cycle of algae blooms, die off and new bloom. Pond Logs and MetaFloc are examples of a nutrient binder. Additionally, flocculants then help to move both algae and suspended particles out of the water column to the bottom by clumping them together, which makes them heavier, causing them to sink. Being at the bottom also starves any surviving algae of the light it needs to grow and reproduce.
Both algaecides and nutrient binders can be used in combination if needed but most pond owners choose to use one or the other depending on their set-up, size and ease of access. We can help you decide which is the right fit for you just call or even better drop by with a water sample.
