Last Updated on December 31, 2019 by Aiden Lindow

What Does Algae Need To Grow?

What does algae need to grow? Well, algae is actually quite a simple aquatic plant, so it only needs a few things in order for it to grow.What Does Algae Need To Grow?

Many people believe that there should be no algae growth in a pond and when it ever does begin to grow people start to panic.

But algae can provide benefits to your pond water if you work with it.

Pond plants, like algae, look natural and can be a healthy food source for your fish.

It also brings oxygen into the water. Algae is the base of any pond and lake ecosystem.

Water clarity should be 24-30 inches deep is the perfect depth so fish can breed and this also helps keep the growth of pond plants in check.

Knowing this, your goal should not be to kill algae, you should work with it.

Try and manage its growth and keep it at a neutral level. Using your amazing maintenance skills will result in a healthier and happier pond.


What Does Algae Need To Grow?


Algae grows best in the sun, experts say your plants should cover 60% of your entire pond.

By doing so, algae won’t grow out of control, but you’ll end up with the perfect amount of algae.

If you can’t figure out how to cover that large amount of your pond I recommend using large-leafed plants.

The two best plants to block out sunlight are water lilies and water lettuce. Water lilies are very common and are in most ponds.

Water lettuce is plant similar to duckweed but with much larger leaves.

Water lettuce looks like a small head of lettuce floating in your pond. Having a mix of these two plants looks very good, and they do a great job of blocking out light.



Many times when people experience an algae bloom it is because there was a change in the number of nutrients in the pond.

An algae bloom is when large amounts of algae grow in your pond in the course of a few days.

By controlling the number of Nutrients that is in your pond you will be able to have the benefits of algae without having it completely overtake your pond.



With warmer temperatures in your pond allows for the growth of blue-green algae to take over your pond throughout the entire year.

Blue-green algae is toxic and can kill all aquatic life. To remove this type of algae, you’re going to need to clean your filter and take out as much of the blue-green algae as you can.

Optimally you would use potassium nitrate, this helps increase nitrate content in your pond, don’t worry, it won’t harm anything else in your pond except the blue-green algae.

Try to keep pond temperature between 65-76 degrees so you won’t have to deal with it.


Water Turbidity

Turbidity is when water loses its transparency due to the presence of suspended particles.

After a heavy rainstorm, you’ll see a rise in water turbidity or more hazy and cloudy water, this is high turbidity.

When your pond has stagnant or slow-moving water where particles sink to the bottom, that is low turbidity.

With low turbidity more sunlight can shine through the water, thus creating the best environment for algae growth.

To create water that has very low turbidity you have to have a good pump and filter system.

The pump and filter will remove any particles that are floating in your pond.

Now that you know exactly the causes of algae, here are some ways to go about keeping algae maintained and at a minimal level. Here are some ideas:


Pond Dye

What Does Algae Need To Grow?

Pond dye is a method that turns green or muddy water into a cool blue, black or any color you can think of.

I’ve written an entire article dedicated to pond dye. Pond dye limits the penetration of sunlight by darkening the water.

In doing so, this will cause the growth of algae to be controlled and reduced.

Using pond dye will also kill any other weeds that might be growing in your pond.

Pond dye also has some pretty cool reflective properties that make the appearance of the water look incredible.


Bacterial Treatments

There are some amazing all-natural bacterial treatments out on the market, such as Microbe-Lift PBL.

Microbe-Lift is focused on getting rid of sludge and dirt as well as gets rid of algae.

I’ve been using Microbe-Lift for quite some time and it works wonders, I’ve never purchased a better bacterial treatment better than this.



Aeration is something every pond needs to have because of the insane benefits.

Firstly and most importantly, it controls the growth of algae. Waterfalls are very common when it comes to aeration.

Aeration is very important because it provides oxygen to the pond.

If a pond has little oxygen algae can be grown very easily and take what oxygen is in the pond away from the fish.


Benefits of Pond Algae

When someone says algae the immediate response is the remove all algae from the pond. While algae can easily overtake ponds and cause brown or green water there are many benefits as long the algae is controlled.


Water Purity

Algae, just like any other plant, take in nutrients and uses them for its own growth.

Algae in your pond will take the unused nutrients from the water and use it for itself.

This will remove the nutrients from the water and help keep water levels balanced.

If there is way too much spare nutrients in your pond, the algae will grow like a rocket and your pond will be taken over by algae.


Water Clarity

Benefits of Pond Algae

Just like before algae will use the excess nutrients in your pond.

The only difference is that by using these nutrients it will prevent decomposing debris from making the water a brown or green color.

Algae filters the water removing any unneeded nutrients or chemicals. If these chemicals and nutrients are removed it will make the water clear.


The base of the Food Chain

Algae is the base of any pond ecosystem food chain.

Algae is eaten by small microscopic animals that become food for small fish. Small fish get eaten by bigger fish and so on.

Algae also promotes the laying of insect eggs such as mosquitoes.

If the mosquitoes get the chance to lay eggs before being eaten, the eggs and larvae are a great source of food for fish in the pond.


What Are Some Common Types Of Pond Algae?

Filamentous Algae

This type of algae is described as long stringy hair and looks like cotton.

This type of algae can form thick greenish-looking mats on the surface of the water.

It is often found in ponds and attaches itself to rocks, logs, and even other plants. Some filamentous algae is bright green and slimy to the touch and look like horsehair.

Also known as string algae, this type of algae can easily take over any pond. This type of algae is known to entangle fish in the hairlike structure. If you see this in your pond I recommend removing this immediately as it can kill your fish.


Planktonic Algae

This type of algae is single-celled and can be found all over the world.

The sprouts are a bright green, pea soup looking and are found in newly established lakes and ponds.

These locations must have it because it is planktonic green growth for a sustenance source.

Planktonic is very beneficial in small amounts as it produces oxygen and is a food source to all the small fish in ponds.


Blue-Green Algae (Toxic)

This is also known as planktonic algae, it is very harmful to all pets and even us humans.

If you do discover blue-green algae in your pond you’re going to need to get rid of it. When these algae bloom, it decreases water quality, produces a bad odor, and produces toxins.

These toxins can cause serious sickness and even death. Toxic algae form when there is a lot of sunlight, warm temperatures, and stagnant water.

Just don’t leave your pond untreated and you’ll be fine.



Algae is not all bad, it has many benefits, just make sure you control the algae and keep it to a minimum.

So, what does algae need to grow? Sunlight, nutrients, temperature, and water turbidity.

If these are kept in check, you shouldn’t encounter a serious case of algae all over your pond.