7 Small Tangs For Your Nano Reef Tank

Long before Finding Nemo and Finding Dory hit our screens, tangs were a staple reef fish in aquariums, but since then aquarists have gone crazy over these colorful, disc-shaped fish. 

Tangs are incredibly unique and stunning fish, and with endless color combinations within the tang group, it is enough for any hobbyist to fall in love with them. 

However, tangs are not the easiest group of fish to add to aquariums, as they can present plenty of challenges – one being the tank size required and their aggressive nature towards other tangs. 

While all tangs start off small, some species can grow rather large, soon outgrowing smaller tanks like popular pico and nano reef tanks. So, before you rush down to your local fish store (LFS), do your homework.

Most tangs grow into large saltwater fish, but that’s not always the case. There are seven small tangs for your nano reef tank that you can easily find, including the smallest tang in the world – the Bristletooth Tomini Tang. Other small tangs include the Squaretail Bristletooth Tang, Yellow Eye Kole, Two-spot Bristletooth Tang, Yellow Tang, Convict Tang, and Mimic Tang.

What Are Tang Fish?

Tang fish come from the Acanthuridae family and are more commonly known as surgeonfish. They originate from the Indo-Pacific region, found cruising along coral reefs in tropical waters. They are extremely popular, particularly smaller tangs because they can be added to nano reef tanks. However, because of their popularity, they are super addictive to collect, and it is usually tangs that sway aquarists to eventually upgrade to much larger reef tanks. 

Should Tangs Be Kept In Nano Tanks?

Whether tangs should be kept in nano reef tanks raises a lot of debate in the hobby. In reality, we do not recommend placing a tang in a nano aquarium without experience. This is because smaller tanks are less stable and therefore more challenging to maintain. 

Nano tanks can also quickly become overcrowded which will stress a tang, increase aggression, and the chances of the dreaded ICH parasite and fish diseases. 

Although tangs shouldn’t be kept in nano tanks, there are some ways you can bend the rules and why you may keep a small tang in nano reef tanks.

Any tank that is 50 gallons or less is considered a nano tank, which is considerably smaller than a regular reef tank. The first reason you may keep a tang in a nano tank is for quarantine purposes. The second reason is for grow-out purposes. If your reef aquarium has larger fish, you don’t want to add a very small tang, as they are likely to get picked on by larger fish.

However, adding small tangs to nano tanks is possible, and if you are set on keeping a tang in a nano tank, there are small captive-bred tangs available. When doing this, it is critical to choose appropriate fish that will thrive in a confined space like a nano reef tank. You should also be experienced enough to maintain good water quality in smaller aquariums.

What Are The Smallest Tangs For A Reef Tank?

Most fish start off small, and tangs are no exception. There are over 80 types of tang fish suitable for aquariums, but some like the Naso Tang which can reach up to 18 inches in length may not be the best choice for a nano reef tank…

Smaller tangs are also undoubtedly beautiful and come in a variety of colors, from vibrant blues to florescent yellows, plus they require less space. The good news is there are many gorgeous small tangs for your nano reef tank. 

#1: Bristletooth Tomini Tang

Bristletooth Tomini Tang


  • Scientific Name: Ctenochaetus tominiensis
  • Size: 6 inches
  • Recommended Tank Size: 70 gallons
  • Care Level: Moderate
  • Diet: Omnivore
  • Temperament: Peaceful but semi-aggressive to newly added fish

Bristletooth Tomini Tangs are the smallest species of tang to encounter in the aquarium world.

When juvenile, Bristletooth Tomini Tangs are tan combined with colorful yellow, blue, and white stripes. As they grow up and mature, the tail becomes yellow and the rest of the body has a golden-yellow tone. 

As they are small, they will cope in nano aquariums if you keep on top of the water quality. We however recommend a 70-gallon tank or larger, as they are active swimmers and can become aggressive toward other tangs if the tank becomes crowded.

#2: Squaretail Bristletooth Tang

Squaretail Bristletooth Tang


  • Scientific Name: Ctenochaetus truncatus
  • Size: 6.5 inches
  • Recommended Tank Size: 75 gallons
  • Care Level: Moderate
  • Diet: Omnivore
  • Temperament: Semi-aggressive

The Squaretail Bristletooth Tang is one of the most colorful reef fish, boasting a rainbow of colors across their entire body. One thing that makes the Squaretail stand out is its short tail, which is flat-edged, compared to one with pointed tips like most tangs. This is where the name truncatus comes from. 

Squaretail Bristletooth Tangs love searching reef tanks for algae to munch on and will not be afraid at joining the algae cleanup crew inside your reef tank. Their bristle-like teeth allow them to sift and scrape any food they can find. 

They are fairly peaceful small tangs, but they will become aggressive towards other tangs and the same tang species, so they are best kept on their own.

#3: Yellow Eye Kole

Yellow Eye Kole Tang


  • Scientific Name: Ctenochaetus strigosus 
  • Size: 7 inches
  • Recommended Tank Size: 70 gallons
  • Care Level: Moderate
  • Diet: Herbivore
  • Temperament: Semi-aggressive

If you are thinking you haven’t heard of the Yellow Eye Kole, you may recognize this particular tank under its other names: Striped Bristletooth or Goldring Bristletooth. 

Apart from its distinguishing bright yellow eye, the Yellow Eye Kole’s has a yellow-colored oval body shape with bright and bold markings which change as the fish matures. As the Yellow Eye Kole matures, it turns a smooth brown color with blue hues with light yellow spots. 

As they can be aggressive towards other tang species, it is best to only keep one Yellow Eye Kole in your nano reef tank.

#4: Two-spot Bristletooth Tang

Two-spot Bristletooth Tang


  • Scientific Name: Ctenochaetus binotatus
  • Size: 8 inches
  • Recommended Tank Size: 75 gallons
  • Care Level: Moderate
  • Diet: Herbivore
  • Temperament: Semi-aggressive

Two Spot Bristletooth Tangs are adorable additions to any nano reef tank. Their striking orange-brown colors with blue lines and distinctive spots on its head, make it a beautiful fish to select. They are often aggressive towards other tangs, but they seem to get on very peacefully with other reef fish. 

As they are active swimmers, we recommend upgrading to a larger tank when they mature and including marine-based seaweed and algae into their feeding regime to reduce aggression and strengthen their immune system.

#5: Yellow Tang

Yellow small tang


  • Scientific Name: Zebrasoma flavescens
  • Size: 8 inches
  • Recommended Tank Size: 55 gallons
  • Care Level: Easy to moderate
  • Diet: Herbivore
  • Temperament: Semi-aggressive – they can be aggressive towards other tangs or fish with the same body shape

Yellow Tangs are staples in reef tanks, and you have likely seen them in your LFS before because they are by far the most popular small tang in the hobby, and likely the most popular reef fish overall.

Their popularity comes from the Yellow Tang’s striking yellow color, bold personality, and ease of care, which makes them suitable if you are a beginner hobbyist.

#6: Convict Tang 

Convict Tang


  • Scientific Name: Acanthurus triostegus
  • Size: 8 inches
  • Recommended Tank Size: 90 gallons
  • Care Level: Intermediate
  • Diet: Omnivore
  • Temperament: Mostly peaceful

Convict Tangs are often disregarded as they are not the most colorful small tangs for nano reef tanks, but they have epic flashy black stripes and a warming personality which you can’t help but fall in love with. The black stripes along their body resemble an old-school prison suit, hence its common name!

The Convict Tang is mostly peaceful, but they will not tolerate aggressive fish and tangs, and the Convict Tang WILL fight back.

#7: Mimic Tang

Mimic (Chocolate) Tang


  • Scientific Name: Acanthurus pyroferus
  • Size: 8 inches
  • Recommended Tank Size: 90 gallons
  • Care Level: Easy
  • Diet: Herbivore
  • Temperament: Semi-aggressive 

The Mimic Tang gets its name from taking on the colors and patterns of angelfish while they are juveniles. This mimicry keeps them safe in aquariums until they mature and change their color to an elegant yellow with blue pectoral and anal fins. 

As Mimic Tangs mature, their coloration isn’t the only thing that changes. When the Mimic Tangs get older, it becomes more aggressive, and they are not afraid to show their brute behavior towards other tangs. Regardless, the Mimic Tang is a unique species that will add plenty of personality to your nano reef tank. 

7 Top Fish For Nano Reef Tanks

You may want to add more than a tang inside your display tank because let’s face it, no coral reef only has one fish! The following fish won’t get too big, they are not aggressive, are reef-safe, and will thrive in nano reef tanks. 

  • Clownfish
  • Pakula Clown
  • Geometric Pygmy Perch
  • Shrimp Goby
  • Flame Hawkfish
  • Yellow-headed Jawfish
  • Banggai Cardinalfish


Before you buy any tang, always know the origin, health, and adult size before adding it to a nano reef tank. There are seven stunning small tangs suitable for nano aquariums, but remember that they may need to be moved to a larger tank as they grow.

  • Darby Bonner

    As a marine biologist, scuba diving instructor, and experienced aquarium hobbyist, I am obsessed with everything from corals to cruising pelagics like sharks, and everything else in between.

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