Purple Algae In Fish Tank. (All You Need To know.)

The algae issue is something that every aquarist faces during their fish-keeping journey. There are numerous types of algae, including green algae, brown algae, and black beard algae.

Some aquarists and beginners notice purple algae in their tanks and get into worry if it can be completely cleaned or not. We will discuss the purple algae in a fish tank in this article. So, let us find out.

There is nothing like purple algae in a tank. It is black beard algae that look purple when they are dead. The primary cause of BBA in a tank is too much lighting and an imbalance co2 level. Adding siamese algae eaters and using flourish carbon solution will help eliminate the black beard algae.

This article will discuss how we can prevent our fish tank from algae and which are the most common aquarium algae. So, let us get into it.

Do purple algae develops in a fish tank?

There are various algae types, including green algae, hair algae, brown algae, and black algae, but there is nothing like purple algae.

It is possible that what you are seeing is actually a black beard alga rather than purple algae.

Black beard algae belong to the red algae group.

The black beard algae, or BBA, is not actually red and varies from dark green over grey and deep black color.

Now, if the BBA algae have developed purple or white color, it means that the algae is dead and can’t spread anymore in your tank.

It doesn’t mean that it will disappear. Instead, you must take the remaining algae out of your tank using a siphon.

Black beard algae grow in a plant with slow growth, like anubias.

It will start to develop from the edges of the plant and slowly take over the entire plant.

Black beard algae will not only stop in plants but will also spread over the rocks and other things in your tank.

You must know that black beard algae can boost up in your tank if the tank is in poor condition, the tank has a too bright light, and the carbon dioxide level is not appropriate.

It is a challenging job to eradicate the algae from the tank.

How to get rid of BBA?

All these ways will help you get rid of black beard algae from your fish tank:

  1. Add a siamese algae eater to your tank.
  2. Add nerite snails to your tank.
  3. Use Flourish excel bioavailable carbon.
  4. Clean the BBA manually by using a scraper or brush.

Add a siamese algae eater.

A siamese algae eater is known to be the best red algae eater in the aquarium world.

Adding them to your fish tank will help you to eliminate black beard algae from your tank.

They are bottom dwellers and can reach up to 6 inches in size. 

Being bottom dweller fish, they will feed on anything they find while scavenging, including dead fish and plants.

Also read: Do Guppy Eat Algae?

Add nerite snails to your tank.

Adding nerite snails to your tank will also help you eliminate the black beard algae from your tank.

Nerite snails are great algae eaters and will feed on black beard algae.

They are peaceful creatures and will not try to harm any of your fish.

You can consider adding nerite snails to your tank, as they will cause no issues.

Also read: Do Goldfish Eat Algae?

Use Flourish excel bioavailable carbon.

Using flourish excel bioavailable carbon will also help eliminate the black beard algae from your fish tank.

Flourish excel will not only help you eliminate the black beard algae but will also contribute to your plants’ faster growth.

It will not harm your fish and plants, so you can use this without any issues.

We recommend reading the instructions before using this so that you can be clear about the quantity and way to use this product.

You can buy it at amazon: Flourish excel.

Clean the BBA manually.

You can also manually clean the black beard algae using a scraper or a brush.

If the plants are covered with BBA, remove them from the tank and use any brush to scrape the algae manually.

However, if the tank is full of algae, you will not be able to clean it using a brush or scraper.

In such cases, you have to introduce algae eaters or use the Flourish excel solution to eliminate the algae.

Also, if the algae are in conditions that both algae eater and chemicals cannot eliminate, you have to clean the whole tank and start it again with a scratch.

What are the most common types of algae?

These are the most common types of aquarium algae:

  1. Black beard algae (BBA)
  2. Fuzz algae (Hair algae)
  3. Brown algae
  4. Blue-green algae
  5. Blanket weed algae

The blanket weed algae are the toughest algae to remove.

It forms like a mat and gets attached to the hair grass, substrate, and other items.

All you can do to remove this alga is by picking them up using tweezers or by your hand.

The blue-green algae use all the nitrogen present in the water.

Excessive organic waste and lack of water changes result in blue-green algae.

Brown algae are also something that we would not like to see in our tanks.

It starts to grow in the substrate and slowly covers the aquarium glass.

Inadequate lighting in your tank can cause brown algae.

You can vacuum the brown algae from the substrate and then use a cloth to clean the glass.

Excessive hair algae also don’t look good in the fish tank.

Imbalance nutrients and low CO2 levels cause hair algae.

Introducing Amano shrimp and siamese algae eater in a tank will help eliminate hair algae.

You can also use a toothbrush to scrap the hair algae from the plants manually.

How to prevent our tank from algae?

Ensure all these things to prevent your tank from algae:

  1. Limit the lighting in your fish tank.
  2. Avoid overfeeding your fish.
  3. Perform a regular water change of your fish tank.
  4. Run proper maintenance of your fish tank.
  5. Introduce algae eaters to your fish tank.
  6. Add plenty of live aquatic plants to your fish tank.
  7. Test the water regularly.

Limit the lighting

Avoid keeping your fish tank in a place where direct sunlight comes for even an hour a day, as direct sunlight promotes algae growth.

If you are using artificial light, make sure not to add too strong light and add what is necessary. 

Also, make sure that the light is not on for more than 8-10 hours a day. 

We recommend using a timer to turn the lights on and off, as it will ensure that the lights are not on for more than the required time.

Avoid overfeeding your fish.

Overfeeding your fish will result in leftovers and more fish waste, increasing phosphate levels.

Phospate can result in algae bloom in your tank, which can make both plants and fish suffer.

To ensure that you are adequately feeding your fish, feed them in a quantity that they can finish eating in one to two minutes.

If you are feeding them once a day, then feed them in a quantity that they can finish eating in three to four minutes.

If your fish takes longer to finish their food, you are overfeeding them.

Also read: Why Is My Fish Not Eating?

Perform a regular water change.

Performing a regular water change will help you prevent the algae in your fish tank.

A water change will decrease the nitrate level in your tank, which plays a role as fertilizer for your plants.

Consider performing a water change of at least 35% weekly to keep the water clean and protected from harmful toxins like ammonia and nitrite.

Run proper maintenance of your tank.

Not only performing a regular water change will prevent the algae.

You have to keep your tank super clean to prevent algae.

Consider cleaning the tank wall and substrate monthly. 

It will help you keep the tank clean, and the algae will not grow.

Also, if you see any algae in your tank, clean it at the very beginning so it can’t spread.

Introduce algae eaters.

Adding algae eaters to your fish tank will help you eliminate and prevent algae in your fish tank.

These are some of the best algae eaters you can consider adding to your fish tank:

  1. Siamese algae eater
  2. Amano shrimp
  3. Red cherry shrimp
  4. Nerite snails
  5. Plecos

All these will feed on algae and will keep your tank clean.

All these creatures will feed on almost all types of algae, like green algae, hair algae, and red algae.

Add plenty of live aquatic plants.

Adding live aquatic plants to your fish tank will help you prevent algae in your fish tank.

Plants also require the same nutrition that algae require to grow.

When you add plenty of live aquatic plants in your fish tank, the plants absorb most of the nutrients, and there is no nutrition left for algae to grow.

Test the water regularly.

If you are using tap water for your aquarium, consider checking it, as it may contain a high phosphate level or elevated nitrates.

If the phosphate or nitrate level is high, you have to use phosphate remover chemicals or change the water’s source and use filtered water.


There are numerous types of algae, like brown algae, green algae, and fuzz algae, but there is nothing like purple algae.

You may have mistaken it for black beard algae.

Black beard algae are algae of the red algae group.

Too much lighting and low co2 level cause black beard algae.

Introducing Black beard algae eaters like siamese algae eaters, Amano shrimp, and nerite snails will help you eliminate it.

Using a flourish carbon solution will also help you get rid of black beard algae.

Avoid too much light and provide adequate co2 in your fish tank to prevent such algae in your tank.

Reference: Wikipedia, Wikipedia

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