Algae in Your Pond? Here’s How to Remove and Prevent It

One of the most common issues that pond owners face is algae – whether it’s string algae waving in the water, blanket weed covering the surface or just tiny green cells turning your water into pea soup. But the good news is that there are plenty of things you can do to tackle it. Read on, and we’ll take you through some of the best methods to try.

What is pond algae

Algae is the green, slippery and sometimes velvety looking vegetation in your pond, to put it simply. It can take many forms: sometimes it has long strings deep into the water (string algae), and sometimes it’s a green scum on the surface. And sometimes it’s a single-celled organism that suspends in the water and turns it green. You might see algae in your pond at any time of year, but it’s most common in the warmer months and anywhere that gets a lot of sunlight. There are hundreds of different types of algae, and phycologists – the scientists who study it – will tell you that they’re quite fascinating organisms. But that’s not a lot of help when you’re dealing with an overgrowth of algal blooms in your pond.

When is algae a problem in a pond?

A certain amount of algae is fine – it’s a vital part of any healthy aquatic ecosystem, and all ponds of all kinds will have at least a little algae. In fact, algae can be a good thing, particularly in natural ponds. Many types of wildlife benefit from it, and it offers a food source for smaller animals such as snails, water fleas, and even fish. In this case, it’s best left untouched. However, excessive algal growth can be a problem in other types of ponds, especially those that are home to fish such as Koi. When it gets out of control and covers a large amount of your pond, algae can cause issues. It can:

• Reduce oxygen levels and increase carbon dioxide levels at night making it difficult for fish, plants, and other pond life to get the oxygen they need to breath
• Block sunlight, thus preventing other plants from growing
• Create bad smells and an unpleasant atmosphere in your garden
• Clog pumps, filters and drains
• Produce toxins that can harm wildlife, in the case of blue-green algae

How to remove algae from your pond

There are plenty of things you can try in order to remove algae from your pond - and stop it from coming back.

1. Scoop it out: Got long strings of algae and big areas of blanket weed? Your first step should be to take a rake or a net and just scoop it out. This will immediately solve a few problems, though it won’t stop the algae from growing back.
2. Install the right pump and filtration system: A decent pump will circulate the water all day long, eliminating stagnant pockets of nutrient-rich water that would fuel algal growth. Pond filters, meanwhile, are designed to do more than capture debris and solids from the water; they also biologically remove excess nutrients, keeping algae at bay. An ultraviolet clarifier, such as the Oase Bitron, is particularly good for tackling green water algae and many unwanted microorganisms.
3. Use a nutrient binder: Algae thrive in areas with lots of nutrients, especially phosphates and nitrogen. So, one way to stop it from growing is by adjusting the nutrient levels in your water. Oase’s PhosLess products – designed to bind and settle out phosphates – can be placed in the skimmer or filter, or applied directly to the water. And don’t worry, when done properly, this won’t affect the health of your fish and plants.
4. Introduce scavenger species: Some animals love algae and will chomp it right up. Adding species such as snails, suckerfish, and even carp and catfish can help naturally reduce the algae levels in your pond.
   Tip: Seek advice from local aquatic shops and pond clubs to find out which critters are best to use in your area of the world.
5. Add more plants: Submerged plants compete for nutrients in the water, which pushes algae out of the game, and aid oxygenation too. Meanwhile, plants that live on the surface, such as water lilies, shade the water below, depriving algae of the sunlight need for algal growth
6. Add a pond dye: Pond dyes turn your water black or blue, which stops the water from absorbing the sunlight that algae need to grow. They’re effective for tackling algae, but be warned that they can also affect other plants growing under the surface.
7. The barley straw trick: A bundle of barley straw in the water can help tackle algae. As the straw decomposes, it can produce a substance that prevents algal growth. It also has the benefit of being a completely natural solution. Be careful though – when used incorrectly, barley straw can actually make algae worse!
8. Use an algaecide: If you’re really struggling with algae and feel like you’ve tried everything, the last resort is to use an algaecide product such as Oase’s Algo Direct. These are incredibly effective at getting rid of all three types of algae.
9. Prevent algae regrowth: Whatever your algae problem is, Oase has the technology to tackle it once and for all. Explore our range of products and enjoy crystal clear water once again.