10 Popular Small Saltwater Fishes You Should Know

Small Saltwater Fish

Keeping saltwater fish is not the easiest thing or it is at least not as easy as keeping freshwater ones. A saltwater tank takes more effort to keep the water clean and balanced, and this is even more so if you have a small one as you will need to have the right small saltwater fish.

Also, freshwater fish are way hardy than most saltwater ones, and this means they will not require a lot of care. Things become even harder for your saltwater fish when you want to keep them in a small or what is popularly referred to as a nano tank as you have to be careful not to overcrowd it while also ensuring the fish you have can live well together.

And besides the extra effort that will be required to find the ideal equipment for your nano tank, you will even need to pay more attention to selecting the best small saltwater fish for the tank.

But, this piece aims to make things easier by recommending 10 nano saltwater fish that will give aquarists an easy time whether they are beginners or highly experienced.

1. Pajama Cardinalfish

Pajama Cardinalfish
  • Experience Level: Beginner
  • Max Size: 3 Inches
  • Temperament: Peaceful
  • Water Temperature: 72-78° F
  • Water pH: 8.1-8.4
  • Aquarium Hardiness: Quite Hardy
  • Min Tank Size: 20-30 gallons

While there are many kinds and types of Cardinalfish, the Pajama Cardinalfish is the most popular type for small saltwater aquariums. The distinctive yellowish face and some brilliant red eyes create a perfect contrast with a spotted body to give the fish a very appealing look.

Pajama Cardinalfish is small but peaceful fish that will grow to around 3 inches when fully matured which makes it perfect for almost any small fish tank. And they can live well with invertebrates and as both individuals and in a school.

Because this fish is quite hardy, friendly, and active (mostly at night) and can adapt to almost any saltwater tank, it will be ideal for both beginners and seasoned aquarists.

These small fish are carnivorous and while a diet of Mysis shrimp and vitamin-enhanced brine will suit them best, they are not picky eaters, and so they will give you an easy time when it comes to feeding them.

2. Neon Goby

Neon Goby
  • Experience Level: Beginner
  • Max Size: 2 inches
  • Temperament: Peaceful
  • Water Temperature: 72-78° F
  • Water pH:8.1-8.4
  • Aquarium Hardness: Extremely Hardy
  • Min Tank Size: 10 gallons

Neon Goby is one of the hardiest small saltwater fish and one of the best saltwater fish for 10-gallon tanks as it does not require a lot of room. Also, it is one of the smallest saltwater fish you can get out there as a fully grown adult will hardly ever grow past 2 inches.

Although the Neon Goby is quite a peaceful fish, it still defends its territory aggressively and will often argue with other gobies, but a mating pair should be more peaceful.

And while in the wild they will typically feed off parasites from other larger fish, in a home aquarium, their diet should consist of things like table shrimp, brine shrimp, and frozen Mysis shrimp.

This fish is generally easy to keep, and you can have it either as part of a community or in a reef as it is naturally a good coral reef inhabitant that enjoys hiding in rocks.

Read More: 5 Best Nano Reef Tanks

3. Clownfish

Clownfish
  • Experience Level: Beginner
  • Max Size: 3 inches
  • Temperament: Peaceful
  • Water Temperature: 73-80° F
  • Water pH: 8.0-8.4
  • Aquarium Hardiness: Very Hardy
  • Min Tank Size: 30 gallons

Clownfish should be at the top of your list when looking for saltwater fish for small tanks as it is one of the most popular options having been made famous by the movie "Finding Nemo".

These small fish will grow to around 3 inches and are quite peaceful except for the maroon clownfish that grows a little larger than this and also tends to be more aggressive.

Generally, this fish is super easy to care for, and feeding it should not take a lot of effort as the frozen foods and dry pellets that it eats are widely available.

Better yet, these striking and colorful fish are quite active and unlike other small saltwater fish, they do not like to hide and will hence make the tank colorful throughout the day.

An amazing fact about the Clownfish is that it is a hermaphrodite as they are all born male and can turn female when they need to which makes them great for those that intend to breed them.

4. Dartfish

Dartfish
  • Experience Level: Beginner
  • Max Size: 3 Inches
  • Temperament: Peaceful
  • Water Temperature: 72-78° F
  • Water pH: 8.1-8.4
  • Aquarium Hardness: Fairly Hardy
  • Min Tank Size: 20 gallons

Dartfish or Firefish Goby as it is also referred to as is a family of small saltwater fish that are known for a charming and more innocent appearance complemented by a bright, colorful body that typically has purple or orange shades.

But what truly makes these fish unique besides the long and eel-like body is the addition of split dorsal fin near the head on some species.

The Dartfish are fairly hardy fish that will adapt to aquarium life fast and hence making them ideal for beginner aquarists. Also, these fairly small fish are quite intelligent and are a peaceful species that seems to do best when kept in a group of at least 4 individuals.

As for feeding, they will need a steady supply of a variety of meaty foods, but a refugium that can give them a continuous supply of plankton would even be better as they will be able to feed on what they typically feed in their natural habitat.

5. Blue Chromis

Blue Chromis
  • Experience Level: Beginners
  • Max Size: 4 Inches
  • Temperament: Peaceful
  • Water Temperature: 72-78° F
  • Water pH: 8.1-8.4
  • Aquarium Hardiness: Very Hardy
  • Min Tank Size: 30 gallons

The Blue Chromis is another highly popular choice with reef aquarists and most love it because besides having a striking look, it is also a very hardy fish that will adapt to an aquarium quickly.

This fish can be kept with most invertebrates and community fish as it is quite peaceful and is hardly ever aggressive even when defending its territory. In their natural habitat, you will often find these fish in a school and for a home aquarium, a small school would also be great.

These reef-friendly fish will require a diet that combines herbivore and meaty foods as they are omnivorous. And these are very hardy fish that can live for anywhere between 8 and 15 years which is longer than most other small saltwater fish.

6. Green Chromis

Green Chromis
  • Experience Level: Beginners
  • Max Size: 4 Inches
  • Temperament: Peaceful
  • Water Temperature: 72-78° F
  • Water pH: 8.1-8.4
  • Aquarium Hardiness: Very Hardy
  • Min Tank Size: 30 gallons

The Green Chromis is quite similar to the Blue Chromis with the color being the most significant difference between the two. It has a perfect green coloring that will look amazing with some good tank illumination.

These fish are mellow and easy to care for and will hence be a great addition to your new saltwater tank, and as the Blue Chromis, it is an active fish that seems to prefer to school and likes to live in a habitat with lots of live rocks.

Although these fish seem to quarrel with some other species in the tank by making a nibbling motion, they are not very aggressive, and they also leave for 8 to 16 years meaning they will last longer than most others.

For the best care, you should feed these fish several times a day and give them a varied diet that should include flakes for herbivores, frozen fish foods, and meaty foods.

7. Catalina Goby

Catalina Goby
  • Experience Level: Experienced
  • Max Size: 2 Inches
  • Temperament: Peaceful
  • Water Temperature: 60-70° F
  • Water pH: 8.1-8.4
  • Aquarium Hardness: A Little Sensitive
  • Min Tank Size: 10 gallons

Catalina Goby is one of the most beautiful gobies you can have on your aquarium.  Growing to a maximum size of around 2 inches, it is one of the smallest saltwater aquarium fish.

This fish has a lovely bright red body adorned by some vertical stripes on the front half of the body and with a vivid blue mask, and so in a well-lit aquarium, it will create a breathtaking sight.

Besides its beauty, this fish also does not require a lot of room as you can comfortably house it in a 10-gallon nano aquarium, and it is also not a shy fish which means it will hardly ever hide under aquarium ornaments.

The Catalina Goby also has reproductive tissues for both genders, and so it can switch to the other gender which is always a good thing for those that intend to breed it.

Although this fish will require an increased level of care and hence making it better suited for experienced aquarists, it is easy to feed as it will accept almost any meaty frozen or prepared foods and even sinking pellet foods or flakes once it gets used to the aquarium.

8. Crown Goby

Crown Goby
  • Experience Level: Beginner
  • Max Size: 2 Inches
  • Temperament: Peaceful
  • Water Temperature: 72-78° F
  • Water pH: 8.1-8.4
  • Aquarium Hardiness: Hardy
  • Min Tank Size: 10 gallons

The Crown or Coral Goby is always a cheerful addition to your saltwater fish tank as its bright colors will make things livelier. Also, these are not shy fish as you will often find them perched out in the open on live rocks or corals.

And while an adult will hardly grow beyond 2 inches, the fish still has a commanding presence in your aquarium thanks to the super large head and stocky shape that make it appear larger than it is.

An aquarium with at least 10 gallons of water and with some branching corals will create the perfect habitat for this fish, but you will need to take extra caution with the kind of corals you have as these fish are known to nip on smaller corals.

It is common for this fish species to spawn in the tank and will do so quite fast, and so if you do not want to end up with more fish than you can manage, it is better to start with one or a couple of pairs.

Also, these might be peaceful fish but in a smaller aquarium system where they are overcrowded, they tend to fight with their kind a lot.

9. Royal Gramma

Royal Gramma
  • Experience Level: Beginner
  • Max Size: 3 Inches
  • Temperament: Peaceful
  • Water Temperature: 72-78° F
  • Water pH: 8.1-8.4
  • Aquarium Hardiness: Hardy
  • Min Tank Size: 30 gallons

Royal Gramma gets its name from the fact that its vibrant yellow and purple colors are symbols of royalty. These fantastic colors mean that this fish will always add a vibrant splash of color to your small fish tank.

Many aquarists love this fish because of both its amazing color patterns and small adult size as it makes it ideal for small saltwater fish tanks.

This small saltwater fish species prefers extensive rockwork caves, and so if you are planning to add them to your tank, you need to plan for this by including caves in the layout.

Overall, these small fish will also be preferred for their hardy and easy to keep nature because even beginners will have an easy time with them, and they also adapt easily to a new aquarium.

When it comes to feeding them, these are carnivorous fish that will require meaty frozen or prepared foods like Mysis shrimp and brine shrimp

10. Orchid Dottyback

Orchid Dottyback
  • Experience Level: Beginner
  • Max Size: 3 Inches
  • Temperament: Semi-Aggressive
  • Water temperature: 72-78° F
  • Water pH: 8.1-8.4
  • Aquarium Hardiness: Very Hardy
  • Min Tank Size: 30 gallons

The gorgeous lavender-colored Orchid Dottyback is a great addition to any reef tank. This beautiful fish has a wonderful personality and for most aquarists, it becomes their aquarium favorite.

To give this fish a good habitat, you will need at least a 30-gallon aquarium and make sure it has numerous hiding places. And it is not a shy fish as it tends to swim in the open once it gets accustomed to the fish tank.

The Orchid Dottyback is classified as a semi-aggressive species as it tends to defend its hiding places aggressively and will also chase smaller fish occasionally and can prey on bristleworms and mantis shrimp.

Feeding this small fish species is also not an issue as they accept most meaty foods such as mussels, planktons, krill, Mysis shrimp and brine shrimp that is vitamin-enhanced.

Note: If you intend to put more than one Orchid Dottyback in the same nano fish tank, make sure you add them together as they tend to show aggression to newcomers. Also, always add them last to your aquarium to prevent this aggression.

Read More: 10 Best Pond Fishes

Conclusion

Choosing small saltwater fish for your nano aquarium needs some careful planning and extra precaution as you need to make sure what you get will be comfortable and will live well with its tankmates.

While the small size of these fish makes many aquarists want to have more of them in the aquarium, this is never a good idea because despite the size they still need to have enough room.

By carefully considering important things like your aquarium size, habitat requirements, fish compatibility, and temperament and with our top 10 recommendations above, you should have an easy time populating your small aquarium.