How to Get Rid of Red Hair Algae in Freshwater Tank {Causes and Treatment Options }

I’m experiencing a terrible problem with red hair algae in my freshwater tank.

I need to know how to get rid of red hair algae in fresh water tank, but the information out there is limited.

This is why I decided to put in more effort to help aquarists like you with a detailed article to reduce or remove red hair algae in freshwater tanks. Join me as we finish them off and return to pristine tank conditions together.

How to Get Rid of Red Hair Algae in Freshwater Tank

Let’s roll up our sleeves and begin right away with:

Reducing nutrients from:

  • excess waste
  • phosphates

Now, we need to:

  • increase CO2 levels
  • limit lighting (extend blackout periods and provide more shade from hardy plants)

My final steps will be to:

  • employ algae eating aquatic life to help get rid of red hair algae.
  • complete this article to learn more and prevent red hair from algae coming back. 

What Is Red Hair Algae?

Similar to green hair algae, this red to dark red type of hair algae has the scientific name, Centroceras clavulatum.

It’s classified as a macro algae and grows at a moderate rate. You can choose to either control it or get rid of it entirely from your tank.

Many aquarists enjoy the appearance of red hair algae compared to other types as long as they can keep it groomed and localized instead of allowing it to take over their entire tank.

What Causes Red Algae In Freshwater Aquariums?

There are multiple reasons why you may have an infestation of red hair algae in your freshwater tank. Some of the main reasons are listed below:

  • high phosphates
  • excess nitrates
  • too many leftovers and detritus
  • low CO2 levels
  • too much lighting
  • not enough beneficial bacteria

This type of string algae begins to grow on rocks, decorations and plants. Red hair algae can out compete your live plants for nutrients in its quest to take over your tank.

Can I Remove Red Hair Algae By Hand?

Not really. Although you might be able to pull out chunks of red hair algae, it will most likely grow back within a few days. Remember to use gloves and make sure to not spread any spores around during your removal process.

You can also trim and cut it with shearers. If you use liquid carbon or phosphate reducing solutions available in fish shops, you can weaken the red hair algae in order to pull out most of it successfully.

In order to prevent red hair algae from returning, you will have to:

  • manage your water parameters
  • increase CO2 levels
  • reduce waste or leftovers to limit its nutrients.
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What Is the Best Way to Remove Red Hair Algae?

It’s best to attack red hair algae through multiple and effective methods instead of resorting to only one approach. The following methods can be used concurrently with one another to get rid of your red hair algae problem:

  • Inject CO2 with canisters or a syringe. 
  • Remove decorations, rocks and plants and dip them into a Hydrogen Peroxide bath. 
  • Add algae eating fish, snails and shrimp. 
  • Turn off tank lights for 3 days.
  • Drop in algae tablets such as, Tetra Algizit.
  • Prevent overgrowth with UV light systems.

We have not been asked to endorse any specific product, but we advocate for following the directions indicated on product labels that boast their ability to get rid of all types of algae such as tablets, liquid carbon or phosphate reducing solutions.

Which Algae Eaters Will Eat Red Hair Algae?

It’s best to employ a clean up crew in your freshwater tank to continuously remove or ingest unwanted algae growth.

Red hair algae is more appealing in color and grows at moderate to low levels making it possible to control it without altogether removing it.

This is when the following red hair algae eaters become most useful:

  • Siamese Algae Eater
  • Rubber-lipped Pleco
  • American Flag fish
  • Chinese Algae Eater (juveniles are better)
  • Mollies
  • Nerite Snails
  • Mystery Snails
  • Malaysian Trumpet Snails
  • Amano Shrimp
  • Cherry Shrimp
  • Cardinal Shrimp

The trick to keeping your red hair algae under control is to limit the nutrients it can receive from excess lighting and leftover food or waste.

Vacuum the substrate weekly and remember to not overfeed your aquatic life. You can also employ strong plants that can outcompete the algae for nutrients.

Which Plants Help Reduce Red Hair Algae?

Unfortunately, red hair algae can grow off live plants in your tank and leave them depleted of much needed nutrients.

Adding the strongest freshwater aquarium plants will create a battle for available CO2 and light and hopefully your stronger plants will win.

Consider the following tough plants to outcompete red hair algae:

  • Amazon Sword
  • Cryptocoryne wendtii
  • Aponogeton crispus
  • Bacopa caroliniana
  • Christmas Moss
  • Vallisneria
  • Java Fern
  • Moneywort
  • Hornwort
  • Rotala Rotundifolia
  • Hygrophilia Polysperma
  • Anubia Nana

It’s best to occupy the tank with a wide range of plants of varying heights. They create comfortable hiding spaces for your aquatic life and create shade to limit the light that any red hair algae can receive.

What Is The Blackout Method For Killing Red Hair Algae?

The blackout method is to simply remove or turn off your aquarium lights for a period of three to five days.

During this point some of your plants may also wither, therefore it is best to keep the hardiest and strongest aquatic plants that are capable of surviving in the dark during this time.

The red hair algae will be weakened to the point where you can manually remove it. In the future, it’s best to manage your light cycle to make sure that your tank is not getting more than 12 hours of tank lighting per day.


We hope that you can use the tips provided in this article to either manage, control or completely remove red hair algae from your freshwater tank.

If you are using hydrogen peroxide, CO2 injections, algae removing tablets or any other product, please be careful to not overdo it.

Rely on your algae-eating aquatic life to assist you. You may enjoy keeping small quantities of well trimmed and neatly maintained red hair algae in certain locations if you find it appealing.


Thanks for visiting and we hope to see you again for another article on algae or any other types of aquatic life that interests you. 

Brian Arial

Brian Arial has kept fish for leisure and worked with fish stores for most of his life. He enjoys writing and caring for aquariums and ponds.