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How To Get Rid Of Cotton Candy Algae Quickly!

Algae can be the bane of many fish keepers lives due to how rapidly it can spread and take over the tank while depleating the water of essential nutrients too.

Although most algae is not intentionally added to the tank, there are some types of algae that are becoming increasingly common within the community that are intentionally being added to an aquarium due to their visual look.

The two main types of algae that fit this category are marimo moss balls and cotton candy algae.

Although marimo moss balls are slow growing and easy to remove if needed, cotton candy algae can be difficult to get rid of once it has been added to your tank either intentionally or accidently so we see a couple of people asking about how they can get rid of cotton candy algae in their tanks each month.

Due to this, we wanted to publish this dedicated article on the topic to try and help as many of our readers as possible who are having problems with cotton candy algae.

What Is Cotton Candy Algae?

Cotton candy algae, formally known as Audouinella violacea is a type of red algae that is most commonly found in the Caribbean.

This algae gets its name from its similarities in appearance to actual cotton candy due to its fluffy and wispy nature.

Cotton candy algae is most commonly found clinging to hard surfaces within the aquarium such as driftwood, rocks or even the glass.

This algae is not to be confused with other types of fluffy red algae that are found in marine tanks such as Ostreobium quekettii which is also sometimes called cotton candy algae.

Cotton candy algae is a type of macroalgae which means that it can grow quite large if left unchecked and can quickly take over the tank.

This algae is also known to release toxins into the water which can be harmful to your fish, inverts and corals so it is important to remove it from your tank as soon as possible.

How Did Cotton Candy Algae Get Into My Tank?

There are two main ways that cotton candy algae can end up in your aquarium.

The first way is if you intentionally added it to your tank.

This is most commonly done by people who want to use this algae as a form of natural filtration within their aquariums as it is known to help with nitrate and phosphate levels or want it due to its unique look.

The second way that this algae can end up in your tank is if it was accidently introduced.

This can happen if you buy live rock or driftwood that has not been properly cleaned as this algae can often hitchhike its way into your aquarium on these pieces of decor.

Cotton candy algae can also be introduced to your aquarium if you do a water change with water that has not been properly filtered or treated as this algae can often be found in tap water.

How to Get Rid Of Cotton Candy Algae!

The first step in getting rid of cotton candy algae is to figure out how it got into your aquarium in the first place.

If you know that you added it to your tank intentionally, then you can take steps to prevent it from spreading such as quarantining new pieces of decor before adding them to your main tank.

If you think that it was accidently introduced to your aquarium, then you need to take a look at your water changing and filtration routines to make sure that you are not introducing this algae into your tank each time you do a water change or add new media to your filter.

Once you have figured out how the algae got into your aquarium, you can then start to take steps to remove it.

The best way to remove cotton candy algae from your aquarium is by manually removing it.

This can be done by carefully siphoning it out of the tank or by using a pair of tweezers to pluck it out.

If the algae is clinging to hard surfaces such as driftwood, rocks or the glass, then you can use a toothbrush to scrub it off.

Just be careful not to scrape too hard as you could damage the surfaces that the algae is clinging to.

If manual removal is not an option or if you have a lot of algae, then you can also try using chemical treatments.

The most common chemical treatment for cotton candy algae is potassium permanganate.

This chemical can be very effective at killing algae but it is also very toxic so it should only be used as a last resort.

Potassium permanganate can also be very harmful to your fish, inverts and corals so it is important to remove them from the tank before using this chemical treatment.

You can also try using other chemical treatments such as hydrogen peroxide or Excel but these are not as effective as potassium permanganate and can also be harmful to your tank inhabitants if used incorrectly.

What Eats Cotton Candy Algae?

There are a few different types of creatures that will eat cotton candy algae.

The most common type of algae eater that will consume this algae is the mandarin goby.

These fish are known for their unique looks and their voracious appetite for algae making them the perfect addition to any aquarium with an algae problem.

Other fish that will eat this algae include the lawnmower blenny, sea urchins, Nassarius snails and hermit crabs.

If you have a reef aquarium, then you can also try adding a few herbivorous corals such as Blastomussa merletti or Xenia spp.

These corals will help to control the algae growth in your tank while also providing your aquarium with some beautiful colors and interesting shapes.

Preventing Cotton Candy Algae From Coming Back!

The best way to prevent cotton candy algae from coming back is to figure out how it got into your aquarium in the first place and take steps to prevent it from happening again.

If you know that you added it to your tank intentionally, then you can take steps to prevent it from spreading such as quarantining new pieces of decor before adding them to your main tank.

If you think that it was accidently introduced to your aquarium, then you need to take a look at your water changing and filtration routines to make sure that you are not introducing this algae into your tank each time you do a water change or add new media to your filter.

You can also try using chemical treatments to prevent the algae from coming back but these should only be used as a last resort as they can be harmful to your fish and other aquarium inhabitants.