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Top Nano Saltwater Fish For A Nano Reef Aquarium


Best nano Aquarium fishNano Saltwater Fish are Ideal for small aquariums of 8 gallons or more. An aquarium is considered a nano tank when it’s about 30 gallons or less. What’s great is that many of these species develop tiny territories within their new fish tank. While they don’t require any specific feeding, we recommend using live rock. That will provide better filtration in a small tank that can easily pollute and also further food source. Small aquariums look easy to maintain, but they are still a lot of work!

As I’ve already hinted at, a smaller tank is much more sensitive to pollutants, which is why I recommend live rock. I actually get my live rock from amazon (crazy)! Check out the best live rock for saltwater aquariums for more info.

Because the tanks are so small, there isn’t enough water to balance out pollutants, and so they become potent. If you’re diligent though, you can still make you tiny tank into a nano powerhouse. Make sure you have a super filter in your nano tank!

Be sure to check incompatibilities before purchasing Nano fish. Some small fish, like short men, suffer from short man syndrome and are aggressive toward other fish!

We love the small saltwater fish, so we’ve compiled a list of our 10 favorite saltwater nano fish, for your nano aquarium tank:

Top Nano Saltwater Fish:


1. Pajama Cardinalfishpajama cardinalfish nano fish tank
Pajama Cardinal Fish get to be about 3 inches (8 cm) in size so that’s the large scale for a nano tank. If you have a 30 gallon tank then these little beauts are ideal. They are not fussy eaters, and are relatively peace loving creatures. They are reasonably priced and generally take a long time to reach full size, especially when in a smaller sized tank.

2. Blue Devil Damsel Fish

yellowtaildamselfishBlue Devil Damselfish – these little guys are on the smaller side of nano fish, which is great, however, they can be very territorial and aggressive. If you do have them – make sure you research their compatibility with other fish and try to limit numbers of males.

3. Coral Beauty Angelfish 

Coral beauty angelfish look like the saltwater version of dwarf gouramis. This slender fish is common on the Great Barrier Reef in Australia, and is also known as the Twospined or Dusky Angelfish. The main body and head are a vibrant, deep royal blue. Intertwined with that color is a sunset hue, they usually have yellow fins which helps identify them. They make the list of top nano saltwater aquarium fish because they are one of the easiest angel fish to care for.

4. Neon Blue Goby

Neon Blue GobySometimes known as the “cleaner fish”, neon gobies look a lot like Cleaner Wrasse, and are very mild mannered. They are fast swimming, but don’t distract or irritate other fish. The Neon Blue Goby, or Neon Goby, is known for its stunning ocean blue racing stripes. These signature stripes begin jsut above the eyes and continue down the length of the entire fish. The Neon Blue Goby is one of the hardiest ocean fish and due to its small stature (only 2 inches long) it makes the prefect addition to smaller nano reef tanks.

5. Coral or Crown Goby

crown goby for small nano fish tankThe Yellow Clown Goby is a delightful addition to any saltwater aquarium. Bright yellow and peace loving, they often take shelter in rocks and coral. They can also be active fish, swimming in the open or playing with other fish. A fully grown adult yellow clown goby will reach a minute 1 to 1.5 inches in size, making it perfect saltwater Fish for a nano reef aquarium.

Small but tough, it’s stocky build and strong fins ensure it isn’t a target for larger species.

6. Firefish Goby

firefish-gobyThe firefish goby has powerful colors, with a pure white head and an amber red rear. It has a longdisticntive fin on the top. Known to have lots of personality, the mild mannered fish is great for its ability to get along well with other species. Only growing up to a couple of inches, the small size and mannerisms make it a top choice for nano reefs.

In its natural habitat, the Firefish goby sticks to small groups just above reefs. They primarily feed of debris and plankton that drift over the reef. Remember, this is very much a reef fish and you’ll need to work hard to provide a safe habitat. Live rock plants and coral are essential. Also, these fish like multiple places to hide, which is best achieved by having the former.

Photo Credit: Drriss & Marrionn

7. Court Jester Goby

court jester goby

The court jester goby originates in the western pacific. Sometimes known as a rainford’s goby, the small fish is timid and peaceful. You’ll need blankets of plants and coral to provide shelter as they are easily startled.

We don’t like ever putting reef or saltwater fish into aquariums without coral, live sand, plants and live rock. In fact, we always have all 4. By definition, that’s their habitat, if you have open ocean fish, then by definition you’ll not have enough space for them to swim.

8. Royal Gramma

royal gramma fishA striking fish with a rainbow color, this fish hides away within coral and rocks and is aggressive towards its own species. It should be very at home in a nano reef due to its small size.

They are very calm around other fish and won’t cause any problems – just house it on it’s own, or with a mating pair.

It will need lots of room, even though it’s a small fish. Don’t house this little guy in anything less than 35 gallons. They have a very meat heavy diet of crustaceans and shrimp (mysis). That adds to pollutants and is another reason to keep this to larger end of nano reefs.

9. Blue & Green Chromis

blue chromis

The Blue Green Reef Chromis is very easy to look after and is a very common starter fish toe beginners. It’s a beautiful fish, quiet and peace loving.

Blue and green chromis both reach sizes around 4 inches, so that might be too large for most nano fish tanks. Please ensure you have suitable space otherwise keeping it will be a cruel and depressing experience for the fish.

10. The Two Spot Goby

The two spot goby, also known as the crabeye gody, is a striking fish, with large dorsal fins marked by large eyes. White and orange, this fish is generally very gental, having the eyes to ward off predators as its main defense. However, it can become aggressive towards other gobys, unless they are a male/female pair.

The goby will need a tank larger than 10 gallons as a minimum. It will need live la

It should reside in a 10 gallon or larger aquarium with live sand as a substrate, and plenty of areas to hide. It will eat a variety of live feed, such as brine shrimp.

11. Don’t keep Clownfish!

We unfortunately no longer support people that have clownfish and have never kept them ourselves. Finding Nemo was released way back in 2003, and subsequently caused a huge decline in wild populations.

That was before we begin a journey into marine and environmental science, and so we were very aware of this tragedy and did not want to support it. We need to ensure numbers increase, but sadly this fish is some famous it’s often the first fish people want to buy.

Furthermore, the clownfish isn’t great to keep in any tank, let alone a nano reef tank. The clownfish isn’t as small as people think either, and can easily reach 5 inches in size. They are also very territorial, with fellow clownfish and also with other species.

Please read our piece on how to ethically keep aquarium fish for more info.

Other Mentions:

There are also many different small invertebrates that are ideal in a Nano tank. They include cleaner shrimps, saltwater snails. Hermit crabs are difficult because they need new shells, so please don’t limit them to a small tank, unless you plan on leaving lots of empty shells about.

Here’s some extra tips of choosing nano saltwater aquarium fish:

  • Make sure you ask about maximum fish size – some nano fish will outgrow your tank
  • Some reef fish need live rock, coral and live food to survive. If you only plan on having a basic saltwater tank, then some fish won’t be an option

I hope you’re able to get started on a great nano reef tank!

About the author

Authority Aquarium Staff

Authority Aquarium Staff writers are experts and aquarium enthusiasts, our in-house marine biologist fact checks all our content and reviews to bring you the best advice for your aquarium health.

1 Comment

  • 1st off keeping i coral beauty in a nano setup is way to small no mater the size of the fish they need at least a 40 even that is kinda pushing it and 2nd captive breed clowns are plentiful and easy to find for years even before finding Nemo there is no reason to get wild caught ones

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