How To Get Rid of Algae in Saltwater Aquariums?

Every saltwater aquarium will go through stages of algae and for some, those stages never seem to end! I’m battling Bubble Algae right now and a Foxface Rabbitfish and two Emerald crabs are slowly destroying it.

When a saltwater aquarium is within its first few years there will be times when it gets unexpected algae outbreaks but there are critters, techniques or products that will allow this ugly mess to be removed and when those do not work patience or better housekeeping will usually do the trick.

Some of the Best Saltwater Aquarium Algae Eaters are:

  • Cerith Snails
  • Nerite Snails
  • Mexican Turbo Snails
  • Mithrax Crabs
  • Conch’s
  • Nassarius Snails
  • Bristletooth Tangs
  • Yellow Tangs
  • Lawnmower Blennies
  • Foxface Rabbitfish

I have gone through many different algae blooms in the life of my saltwater hobby and I always researched the best way to tackle each outbreak with pretty good results.

In this article, I’m going to go through some of the most common types of algae and discuss the best animals, products, or methods to deal with each algae so that you can bookmark this and use it as a reference ready for when the next algae rears its ugly head!

Before we get started you can find a great selection of snails, crabs, invertebrates, and fish to help you control your algae and reference while reading this article.

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What Are The Most Common Types of Nuisance Reef Tank Algae?

At some point you will find one, some or all of these appear in your aquarium over its first few years. Some of them are just part of the aquarium ecosystem settling down and some are nuisance hitchhikers!

  • Film Algae
  • Hair Algae
  • Diatoms
  • Dinoflagellates
  • Bryopsis
  • Cyano
  • Bubble Algae

Let’s look at each of these individually to see how best to tackle them…

Eliminating Film Algae

The green ‘Film’ that coats your glass! You will always have some of this no matter how clean your tank. How fast it grows will depend on each system. Direct sunlight can help to fuel its growth!

Film Algae

Best Ways To Deal With Film Algae

1. Techniques:

It is so easy to remove using a Magnetic Algae Scraper, especially one with a razor blade attachment. I clean my glass every 2-3 days and the blade just scrapes it off in sheets, which my fish then go nuts on, especially my Yellow Tang.

You can find a Great Selection of Algae Scrapers Here at for every sized aquarium. I have used the Magfloat for years and the Flipper is also a great alternative!

NOTE: Whichever glass scraper you purchase make sure it is for glass or acrylic. Using a glass scraper on an acrylic aquarium will scratch it instantly! Trust me I have seen it done many times!

— Sunlight —
If your aquarium gets direct sunlight then it will help to fuel Film Algae. I have one corner that gets a tiny bit of direct sunlight first thing in a morning and that corner is always heavier with green.

By keeping curtains closed or initially setting up your aquarium out of direct sunlight will help keep Film Algae to a minimum.

2. Algae Eaters:
  • Cerith snails – Cerithium sp.
  • Nerite snails – Nerita tessellata
  • Astrea snails – Astrea tecta
  • Turbo snails – Turbo sp.

These are all great for munching on this type of algae and you will see they leave interesting tracks all over your glass. They will not keep your glass completely clean, but they do help. The algae also feeds them as they scavenge for waste and uneaten food left around your aquarium.

Cerith Snails

The snails will help to keep it at bay on the rocks and other places you may struggle to reach without a scraper, but they will never be able to keep your aquarium free of it.

Between scraping every couple of days (I can scrape my whole tank in under 2 minutes) and the snails munching it off the rocks you should never have a film algae problem.

3. Products:

Film Algae is such an easy algae to keep on top of there is no real demand for a single treatment to be developed to tackle it. Between regular scraping, avoiding sunlight, having good quality source water (more on this later), Film Algae is one of the easiest to deal with.

Eliminating Hair Algae

One of the most common nuisance algae types and you will be sure to experience it at some point.
It’s hair like appearance gives it its name. It will grow mostly on rocks and equipment and can grow fast!

Green Hair Algae

Best Ways To Deal With Hair Algae

1. Techniques:

— Picking —
Manually getting your hands in there and picking is the fastest way to remove this stuff and the second you see it you need to try and remove it all before it has chance to spread, then leave the livestock and clean-up-crew to pick at the remains and bits you cannot reach.

— Rock Removal —
If you are lucky enough to have this stuff first show up on a small piece of rock that has no corals on it and it can be easily removed then remove it and bleach everything on the rock. It is far easier to deal with a small rock than an aquarium full of this stuff!

2. Algae Eaters:

For smaller and also large aquariums I recommend:

  • Scarlett Hermit Crabs – Paguristes cadenati
  • Emerald/Mithrax Crabs – Mithrax sculptus
  • Lawnmower Blenny – Salarias fasciatus
  • Tailspot Blenny – Ecsenius stigmatura
  • Cherith Snails – Cerithium sp.
  • Fuzzy Chitons – Acanthopleura
  • Conch’s – Strombus sp.

These are great at mowing this stuff down. If Hair Algae is growing on your sand bed, a Diamond Goby (Valenciennea puellaris) will keep your sand pristine.

For Larger Aquariums over 75 gallons I recommend:

  • Foxface Rabbitfish – Siganus vulpinus
  • Yellow Tang – Zebrasoma flavescens
  • BristleTooth Tang – Ctenochaetus tominiensis
Yellow Tangs
Yellow Tangs – Beautiful & Voracious Algae Grazers!
3. Products:

— Vibrant Aquarium Cleaner —

Many aquarists seem to be getting very good results from a fairly new product called Vibrant Aquarium Cleaner by Underwater Creations.

Vibrant uses multiple strains of bacteria to attack the algae from different angles. One of the bacteria strains targets the Nitrates and Phosphates that feed your algae and turn them into biomass to be removed via your Protein Skimmer or water changes.

This product is also designed to work on any problem algae, according to the manufacturer.

You can read the forum thread HERE on Reef2Reef where Jeff the owner comes on and joins in the conversation regarding it! – Cool!

“Vibrant is a true beast and we have not yet come across a algae that Vibrant can not beat out. Below I will list a general timeline of how fast Vibrant works on frequent algae strains that cause issues in reef aquariums”.

Cloudy/hazy Water– 1 dose
Diatoms – 1-2 doses
Cyanobacteria – (Yes, it will outcompete another bacteria) 1-5 doses
Dinoflagellates – 2-5 doses
Bubble algae – 3-8 doses
Hair Algae – 3-5 doses (depending on species of hair and how bad the infestation is)
Turf Algae – 8-20 doses ( again, depending on species and how bad the infestation is)
Bryopsis – 6-30 doses ( again, depending on species and how bad the infestation is)

Jeff Jacobson
Owner – Underwater Creations, Inc.

TBR Recommends

Vibrant Aquarium Cleaner comes in 8oz and 16oz bottles.

This great product is getting fantastic results and the many owners in the forums are confirming this!

Eliminating Diatoms

Diatoms look like a brown dust covering your sand and rock. They are likely to appear just as your aquarium is finishing its initial cycle and will die off in time. They are fueled by Silicates which can come from rock, sand or some plastics.

Best Ways To Deal With Diatoms

1. Techniques:

— Blasting —
Using a turkey baster to blast the rock and sand will keep them suspended in the water which will then be removed by the mechanical filter. This is especially helpful just before you do your regular water changes. Using a gravel/sand vacuum is also a great way to remove a good portion of them during the water change.

— Patience —
Diatoms will dissipate once the silicate have been consumed but in the mean time good flow, and good maintenance will help this stage pass within a few weeks. If you add new rock or sand be prepared for a possible bloom again.

2. Algae Eaters:
  • Nerite snails – Nerita tessellata
  • Cherith Snails – Cerithium sp.
  • Margarita Snails – Margarites pupillus
  • Nassarius Snails – Nassarius sp.
  • Mexican Turbo Snails – Turbo fluctuosa
  • Fuzzy Chitons – Acanthopleura

Although Diatoms do not seem to be that appetizing for many aquarium inhabitants, those listed above have been known to feed on any patches they find. They can be hit or miss but worth a try if the Diatoms do not seem to be diminishing on their own.

Diamond Goby
Diamond Gobies are Great Sand-Sifters!

If the Diatoms are growing on your sand bed, a Diamond Goby (Valenciennea puellaris) will keep your sand pristine by their regular disturbance of the sand as they sift it for food.

3. Products:

— Good Quality Source Water —
Many homes have city or well water that can be high in Silicates which fuel Diatoms. By initially filling and using high-quality RO/DI water for your water changes and top off water you can reduce the number of silicates present in the aquarium.

This may not fully prevent the aquarium from getting Diatoms, but it will certainly speed up the amount of time it takes for them to disappear!

You can find a great selection of RO/DI water filters Here at This will be one of the best investments you ever make for your aquarium and if you want to know more about these filters, please see my article in the Further Reading section at the end of this post.

— Ultraviolet Sterilizers —
Diatoms are not really a plant-based strain of algae, but a single-celled microscopic organism and because of this they can have their DNA mutated by passing them through a UV aquarium filter.

By mutating the DNA it prevents the cell from reproducing and thus helping to reduce the amount of outbreak you see in the aquarium.

You can find out more information about UV Sterilization Filters at the end of this post.

— Vibrant Aquarium Cleaner —
According to the manufacturer, 1-2 doses of Vibrant should help clean up the Diatoms. I’ve not been fortunate enough yet to try this on Diatoms as my outbreak was many years before this product release, but it gets great reviews on the forums!

Eliminating Dinoflagellates

This algae is a brown/golden looking mat that can quickly grow over sand and rocks. It will have long hair-like strands coming from it in places.

It can be very difficult to remove because nothing eats this stuff!


Best Ways To Deal With Dinoflagellates

1. Techniques:

— Increasing Flow —
Increasing the water flow in your aquarium can help prevent this algae from settling and taking hold. Adding additional wave makers to help prevent flow dead spots can really help.

— Maintenance —
If the aquarium maintenance has stopped being as regular as it should be, then getting back into the cleaning routine will help. Regular blasting with a turkey baster, vacuuming of the sand bed, and water changes will help keep this algae to a minimum until it runs its course.

2. Algae Eaters:

This stuff just does not seem to be appetizing to any animal we can put in our reef! The only one suggestion I have is the Diamond Goby. They do not eat it but he constant sifting of the sand will at least keep the sand bed free of this ugly stuff.

3. Products:

— Vibrant Aquarium Cleaner —
2-5 doses of Vibrant should help clean up the Dinos. Again, I’ve not been fortunate enough yet to try this but it gets great reviews and could be a cheaper option to try after the options above.

— Protein Skimmer —
If your aquarium is running without a skimmer or a low-quality one, then I highly recommend you upgrade to a well-reviewed, high-quality protein skimmer.

Being one of the most crucial filters for a saltwater aquarium a skimmer will help remove this stuff from your tank once you get it into the water column with regular maintenance.

If you are unsure about Protein Skimmers, what they do, and how to select the right one, check out my article in the Further Reading section.

— Refugium —
Refugiums are a device that can be installed on the aquarium where you can grow macroalgae like Cheatomorpha in a controlled way. By growing ‘Cheato’ it outcompetes the Dinos for the same nutrients and helps minimize and prevent longterm reoccurrence of most algae, not just Dinos.

In Sump Refugium
A Typical In-Sump Refugium

Once the Cheato mass becomes too large for the refugium, you just remove half the mass and throw it away. By doing this you have removed many of the nitrates and phosphates the Dinos and other algae are requiring to grow.

Eliminating Bryopsis Algae

This is a ‘fern-like’ algae and it is one of the most stubborn nuisance algae to remove from your aquarium. It will grow in small clumps to begin with but then spreads. It usually enters our aquariums as a hitchhiker on Live Rock or Frag Plugs.

This is an algae I had been battling on and off for years. It just came and went for no apparent reason. It is not unsightly, but it can begin to take up coral real estate if left to grow.

Best Ways To Deal With Bryopsis Algae

1. Techniques:

The only way to stay ontop of this pest during treatment is to manually remove as much of it as you can with your fingers and throw it in the garbage. You will not be able to get it all as the root will remain and allow it to grow again and there are the areas that you cannot physically get to.

By manually removing as much as you can it allows the chemical treatments to work on less of the Bryopsis and hopefully eradicate it faster.

2. Algae Eaters:

Nothing seems to touch this stuff! I mean nothing! I’ve tried and researched what other aquariums have tried and some livestock may munch on it for a few days and the not touch it again. Very annoying!

3. Products:

— Vibrant —
Many aquarists are giving Vibrant great reviews on ridding their aquarium of Bryopisis. Again, I have not had the opportunity to try this product yet as all my nuisance algae blooms were battled for a long time many years ago – Typical!

I would defiantly give this a try before using any of the other methods listed below.

— Kent Tech-M Magnesium —
This is how managed to overcome my Bryopsis Algae, but it took forever!

Keeping high levels of Magnesium (over 1600ppm) in the aquarium using only Kent Tech-M Magnesium seems to slowly melt this stuff away. There apparently seems to be an ingredient in Kent Tech-M that works on the Bryopsis. Many aquarists have tried other magnesium products and nothing happens.

This technique/product requires persistence but does work – Oh and don’t run out of Tech-M halfway through or the Bryopsis comes back! I found that out the hard way!

— Fluconazole —
Fluconazole is a treatment intended for fish infections and diseases but it has been found to be a great treatment for the eradication of Bryopsis. Fluconazole works by blocking the cellular paths within the cells of the Bryopsis plant.

By blocking these paths, it impedes the distribution of a sterol that is similar to Cholesterol in humans. Without this sterol, the cell walls break down and the plant dies.

— Hydrogen Peroxide —
The underdog of fixing many problems that most people never know about. Hydrogen Peroxide is a true giant of the things it can do and one of those is beating Bryopsis in our aquariums.

The only drawback to using this method is for it to truly work you need to be able to remove the infested rock from your aquarium. This can be a quick, cheap fix if you have a nano aquarium or a smaller aquarium with a minimalist aquascape but for those of you with large aquascapes or rocks cemented together, this treatment is probably one to skip.

For more detailed information on Byropsis and how to beat it using all these methods, I wrote an article specifically on it. You can find it here:

Getting Rid Of Bryopsis Algae – All The Methods!

Eliminating Red Slime Algae

Probably one of the most common pests that every aquarist will come across – Red Slime Algae or Cyano Bacteria as commonly known.

It gets its name from the slimy appearance it creates over everything. Sand, rocks, corals!


Cyano as it is commonly referred to, is actually a bacteria rather than an algea, but because of that it makes it fairly easy to treat.

It can show up as dark red, purple, dark brown, and even black, it really all depends on the lighting you have.
The Cyanobacteria cells will reach a point where the aquarium is just right to allow the bacteria to bloom.

If you let the bacteria run its course it will consume all of its food source and die out – Providing you don’t go adding more detritus, phosphate, or nitrates into your aquarium.

Best Ways To Deal With Red Slime Algae

1. Techniques:

— Improving Flow —
Areas of low flow in the aquarium can allow for Cyano to take hold. It finds it hard to attach to rocks and sand if your tank has a high water flow. By changing the positioning of your powerheads and wavemakers, or even adding an additional pump you can really help to remove this stuff.

— Reducing Its Food —
Cyano loves nitrates and phosphates and the main causes for high levels of these elements are:

  • Over feeding
  • Over stocking
  • Lack of maintenance
  • Poor source water
  • Low quality foods
  • Irregular water changes

By addressing these issues first you will not only help prevent the spread of Cyano but many other nuisance algae too.

— Vacuuming —
Just before doing your regular water changes vacuuming the sand bed and blasting the rocks with a turkey nature will allow the cyano to be removed or blown into the water column for the filtration to remove it or be taken out during the water change.

I find a battery-operated gravel vacuum can work well for sucking up this stuff into a mesh bag/screen for removal in between water changes can help, especially if you hate the unsightly look it gives your aquarium

This sand/gravel vacuum from Eheim on is a great option.

2. Algae Eaters:

Another pest that nothing seems to touch! Being one of the most common pests it would be awesome if there was a fish or snail that would eat it but I have not found anything that goes near it!

From my research, some snails MAY nibble on it from time to time but they do nothing to help eradicate this stuff. Nothing I have in my tank even looks at it!

3. Products:

— Chemiclean —
The only brand I have personally tried and had success with has been Chemiclean by Boyd Enterprises. Some Cyanobacteria removal products use antibiotics to kill the Cyanobacteria cells, but this can also kill your helpful Nitrifying Bacteria cells too!

Chemiclean is not an antibiotic-based treatment and will not harm other cells in your aquarium. This, along with the track record and great reviews were the reasons I selected to use it – And it worked very well!

Be sure to read the directions carefully and follow them to the letter as using Chemiclean will send your Protein Skimmer nuts and cause it to overflow. It could also cause a drop in your oxygen level in the aquarium water. A simple air pump and airstone will help prevent this drop.

This is one of most commonly used products to treat Cyano and a little goes a very long way!

— Vibrant —
We are starting to see a common product appearing in these sections and before long it may be the go-to product for ANY algae/bacteria bloom in the aquarium!

1-5 doses is all that Jeff is estimating to get Cyano cleared up so I will only find out if a get another outbreak then I can test his statements.

One to try for sure though, and if it does nothing in your aquarium, Chemiclean should always work!

Red Slime Algae was another pest that needed its own in-depth article with instructions on how to deal with it. You can find my article here:

What Is Red Slime Algae? Easy Ways to Prevent & Eliminate It

Eliminating Bubble Algae

Green algae bubbles that appear singularly or in mass in your aquarium. They can be a battle to overcome as they release spores that reproduce when they burst.

These have been my nemesis but were slowly beaten off with a variety of methods!

Bubble Algae

Best Ways To Deal With Bubble Algae

1. Techniques:

— Manual Removal —
They can be tough to remove by people without nails or fat fingers like myself. The trick is to grab the bubble from its stalk and pick it off without it bursting. This can be an endless routine as it seems to grow back as fast as you can pick it.

One thing to be cautious of with Bubble Algae – To which I almost found out the hard way, is that it can impede water flow if allowed to grow unnoticed in overflows or return chutes/pipes of Hang-On-Back equipment!

Bubble Algae in my Reef!

— Diligent Inspection —
Coming into your aquarium as a hitchhiker on a coral frag plug is by far the most common way it enters our tanks. Very careful inspection, dipping and if possible, frag transplant to a clean plug, is the only way to minimize the chance of it getting in.

I thought I was diligent enough but apparently not as this was the only way it could have entered my reef! My inspection and coral quarantine methods soon changed!

2. Algae Eaters:

For small Aquariums:

  • Mithrax/Emerald Crabs – Mithrax sculptus
    (Get the females as these seem more attentive)

For larger Aquariums over 75 gallons:

  • Foxface Rabbitfish – Siganus vulpinus
  • Vlamingi Tang – Naso vlamingii
  • Convict Tang – Acanthurus triostegus
  • Desjardinii Sailfin Tang – Zebrasoma desjardinii
  • Achilles Tang – Acanthurus achilles
  • Powder Brown Tang – Acanthurus japonicus
  • Purple Tang – Zebrasoma xanthurum
  • Naso Tang – Naso Elegans
  • Sohal Tang – Acanthurus sohal

Some of the Tangs listed above require very large aquariums so please ensure your tank is big enough for your intended purchase before buying. You can see the recommended tank size for each Tang Here at

Foxface Rabbitfish – Bubble Algae Machine!

Out of the animals listed above, I personally found great success with a couple of female Emerald Crabs and the Foxface Rabbitfish. These things mowed down my Bubble algae in weeks once I finally found they were good to try, and it’s never returned!

3. Products:

— Vibrant —
Well no surprises here! 3-8 doses should get it gone. Man, I want to get an algae outbreak now to see if this is as good as everyone says it is! It’s surely going to be in the maintenance bottle section of my shelves ready for when some pest shows up!

Because of my seemingly endless battle with Bubble Algae I wanted to pass on the animals and experiences I had learned to others so I wrote its own article. You can find my article here:

What Is Bubble Algae? – Tips For Eradication

Why Are You Getting Algae An Your Aquarium?

Now that we have covered most of the common nuisance algae there are several things we need to understand about algae.

You will always get algae in your aquarium and that’s just part of the ecosystem, but its how you control and maintain it is the key to an algae-reduced reef tank. Not counting the pests like Diatoms and Cyano, algae is a plant-based organism that requires light and nutrients to flourish. Nitrates and Phosphates are two of the biggest nutrients that can cause you to have sudden outbreaks in your seemingly clean aquarium.

There are many ways that our aquariums get increasing levels of both nitrates and phosphates and it is up to us as the owner to address those problems if you ever want to stop having outbreaks. Two of the most common ways that algae seems to bloom are :

  1. Poor source water that is full of algae rich nutrients to fuel any algae hiding in small numbers
  2. Algae spores hitchhiking into our aquarium on Live Rock or Coral Frag Plugs that are not carefully inspected before insertion.

Before you start purchasing animals or products to help you remove the algae, first you need to try and reduce the causes of it in the first place to prevent it coming back after the eradication has taken place.

These two articles I wrote should be your first point of call on addressing each nutrient:

  1. 12 Ways to Reduce Nitrates in a Saltwater Aquarium
  2. How To Lower Phosphates In Your Saltwater Aquarium

The second set of articles I highly recommend address increasing the quality of your source water and how to inspect and clean coral frags:

  1. How To Select An RO/DI System For Your Aquarium
  2. How To Dip Corals – Easy Steps To Success

To Finish

Unfortunately, you are going to get algae, and being prepared with the knowledge on how to prevent, minimize and tackle each pest will help you stock your aquarium and create a maintenance routine that will ensure the chances of serious infestations are minimal.

I have always tried to use a natural way to remove the pest before adding a chemical to my tank, but sometimes chemical warfare is the only way. I think for many of us a bottle of Vibrant Aquarium Cleaner sitting on the shelf will be a great treatment to have to fight the pest before it has a chance to take hold and cause weeks if not months of persistent work to overcome.

Battles with algae will be overcome and your aquarium will look beautiful once again, just stick at it and be sure to diligently inspect ANYTHING before it goes into your tank!

If you wish to get a copy of my Recommended Aquarium Maintenance Schedule to help you plan a great maintenance routine then check out these guides right here:

Further Reading

Just in case you wanted to keep reading I highly recommend the following articles:


Hi, I'm Richard and I have been an avid aquarist for over 30 years with a passion for Saltwater Aquariums. I love to pass on my knowledge to help others get the same amount a pleasure out of this hobby as I do. View my About Me page to find out more about me & my mixed reef aquarium.

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