15 Nano Reef Tank Fish – #9 Is a Wild Card!

15 Nano Reef Tank Fish – #9 Is a Wild Card!

15 Nano Reef Tank Fish – #9 Is a wild card!
Have you ever wanted to keep saltwater fish but worried about the size of the tank you’ll need or the amount of room you have to house one? Well, we have the perfect answer! A nano reef tank, in this post we’ll show you the Top 15 Nano Reef Tank Fish which would be perfect for your small saltwater tank.
Not recommended for beginners but perfect for anyone who already has some knowledge of saltwater aquarium requirements. The main challenge is water quality in such a small space and resisting the urge to rush and overstock your new nano reef system.
Nano reef fish specimens must be chosen carefully to avoid overcrowding. Small fish, with the maximum adult size of only a few inches, are the best choices. They must be introduced slowly, only a few fish at a time over a period of several weeks.This will enable the water quality to balance out and your filtration system to adjust to the increased levels of pollutants.
What is a nano reef tank?
A nano reef system is a small saltwater tank of typically 25-30 Gallons containing small saltwater fish, invertebrates and Corals and designed to look like a section of the natural reef system for a fraction of the price of a main saltwater tank. These are perfect for smaller spaces and bedrooms. They are less expensive and easier to set up than larger reef tanks.
Don’t be fooled into thinking you can’t get a natural looking reef tank in a very small space. Take a look at the tank below. It looks incredible, I’m sure you’ll agree and this tank is only 34 Gallons!
The number one issue with nano-reef systems is water quality. You’ll need to perform weekly water changes of around 10-20%. In a nano aquarium, this is only about 2-3 Gallons but even this small amount is vital. The temperature change in a nano aquarium when conduction water changes are the main area of concern.
These small aquariums are more susceptible to changes in water quality and temperature because they contain a smaller volume of water. When water-quality issues or temperature changes occur, they can progress quickly and place great stress on the system and can ultimately result in complete failure and loss of life.
There are even smaller saltwater tanks called Pico Reef Tank which is typically 5 gallons or less. These are definitely not for the faint-hearted and require a lot of care and attention. We’ll leave this topic for another day.
Once you have purchased your new nano-reef tank and set it up correctly ensuring all the water qualities are correct then you can start to think about introducing some lovely fish, invertebrates, and corals. In this article, we’ll look at the perfect fish for your new tank.
Getting that water quality correct is really important. For salt, I recommend this Instant Ocean sea salt that you can get on Chewy.com. You’ll also want some of this Fluval Conditioner to condition regular tap water to make it suitable for fish.
Many people will say that a nano reef tank is more about corals and invertebrates than fish and to some extent this is true, but we feel with the correct information you can find the perfect saltwater fish to compliment your corals and invertebrates giving the tank a more natural look.
Let’s take a look at our Top 15 Nano Reef Tank Fish
In no particular order, our top 15 nano reef tank fish are listed below. Selected for a number of reasons, color, size, care level, reef compatibility, and price. These fish will complement and add value, interest and help the eco-balance to your nano reef tank.
# 15 Green Dragonet Mandarin (Synchiropus picturatus )

Scientific Name Synchiropus splendidus
Size 4” Max
Tank size 30-40 Gals minimum
Reef Compatible Yes
Diet Carnivore
Temperament Peaceful
Origin Western Pacific, Australia, Philippines
Care level Moderate
Family Callionymidae
Temperature 72-78f
PH Level 8.1 - 8.4
Specific Gravity 1.020 - 1.025
Cost $30-$50
This amazing fish was first discovered by Albert Williams working in the Philippines in 1927 and has since become a firm favorite with saltwater hobbyists and it’s not difficult to see why.
They get their name Mandarinfish from their extremely bright colors evoking the robes of imperial Chinese mandarins. These amazing looking fish are part of the perciform family Callinymidae, the dragonets which have
10 genera and over 180 species within that group. Often called a Mandarin goby due to their body shape, but that it the only resemblance between the two. The mandarin is firmly placed in the Dragonet family.
Their amazing patterns and colors are the main attraction with this fish and the males can be distinguished by their large dorsal fin. Three type of mandarins are commonly sold in the aquatic trade, red mandarins, Green and the spotted mandarin.
Mandarins are reef dwellers and move very slowly around the tank, therefore, making them an ideal saltwater fish for a small nano aquarium.
See Which Fish Food We Use Here!
The number one difficulty in keeping mandarins is their diet. Mainly feeding on live copepods and amphipods, you’ll need to ensure a constant supply is given to ensure their survival. Many mandarins introduced into a home aquarium often don’t last longer than a week or two due to the lack of live foods within their new home.
Many Mandarins introduced into a new aquarium simply refuse to eat, maybe due to stress or maybe because the food offered is not suitable. We always recommend asking to see the fish feeding in the store before you purchase one. Then you can buy some of that same food when you purchase the fish giving you the best chance to help you fish eat from day one.
You will need to buy live copepods to feed them even if you have a refugium system that you grow copepods in they will make short work of eating all you can grow and you’ll still need to buy more to feed them. This can be an expensive food source but is vital for their survival.
Very peaceful fish growing to a maximum size of around 4″.
Even with their difficult feeding habits, these fish make the perfect nano reef tank fish. They are only classed as difficult to keep due to their diet. You will have no issues with the size of your nano tank, around 20-30 Gallons is fine and they will show no aggression to other fish. They are also reef safe and will not eat or harm any corals or invertebrates. Ensure their tank mates are of similar nature as they fish do not like to be stressed or receive too much attention from others. They are at their happiest just searching the live rock for foods and exploring holes and caves.
Read our full review of the Green Mandarin Dragonet.
#14 Sixline Wrasse

Scientific Name Pseudocheilinus hexataenia
Family Labridae
Origin Indian Ocean and the western Pacific Ocean
Temperament Semi-aggressive
Care Level Easy
Diet Carnivore
Reef Safe Yes
Size 3” Max
Tank Size 25 Gallons+
Price $20
The six line wrasse, Pseudocheilinus hexataenia is found in the coral reefs of the Indian Ocean and the western
Pacific Ocean at depths between 1-34 m. This very small wrasse which grows no bigger than 4″ is perfect for any nano aquarium and is totally reef safe.
One of the most attractive things about this fish to beginners is how hardy and disease/parasite resistant they are making them the ideal nano fish for beginners.
These fish can be semi-aggressive and if you’re going to add them to a tank with very quiet and peaceful fish like
Mandarin Dragonets or Clownfish then make sure you add the wrasse last. That way they won’t get too territorial when new fish are added to the aquarium.
This beautiful fish should be housed as a single wrasse unless you have a very large aquarium. They have been

known to pick on and harass sick or poorly fish so keep a close eye on them.
Their coloration of Orange and Blue lines and green tail make them attractive to all aquarists new and old.
Inexpensive, hardy and interesting to watch, these fish are always a good choice for smaller nano aquariums.
Feeding these fish should not prove to be an issue. They will accept most dried flake foods and live foods like
Brine Shrimp, Mysis Shrimp, and Bloodworms. After introducing one to your aquarium it may take a day or two for them to eat dried foods but you’ll find they will nip and eat foods from your live rock straight away. They won’t harm corals or invertebrates hence making them reef safe.
Throughout the day these fish will swim around searching for pods/micro fauna all day long to eat. At night, they make a mucous bubble around their body and wedge themselves between rocks and sand. This disguises their scent so they can be safe from other predators. As soon as the lights come back on normal activity with resume and they’re quickly back on the hunt for food.
Adding the Six Line Wrasse into our Top 15 nano reef tank fish list was a no-brainer! Every nano tank I’ve ever owned has had one of these fish in. A good mixture of bottom feeder, rock-dwelling, and open water swimmers adds interest to your tank. These fish will certainly add excitement and interest into your aquarium.
# 13 Blue Spotted Jawfish
Scientific Name Opistognathus rosenblatti
Family Opistognathidae
Origin Gulf of California and Mexico Scientific Name Opistognathus rosenblatti
Temperament Semi-aggressive
Care Level Medium
Diet Carnivore
Reef Safe Yes
Size 3-4” Max
Tank Size 30 Gallons
Price $120
The Blue Spotted Jawfish makes a fascinating addition to any mature reef aquarium, this fish is full of character and will make an interesting addition to any nano reef tank.
First discovered in the Tropical Eastern Pacific in 1991 by Allen and Robertson, this fish has since become a staple fish in many nano aquariums.
Providing you give these fish the correct environment they will thrive in a nano reef tank. In the iwld, they can be found in and around the Gulf of California and Mexico (also known as the Sea of Cortez), at depths between
10-28m (30-100ft). The waters in this area are colder than the waters where most popular saltwater fish come from, and this must be taken into account if planning to keep this species in the home aquarium. In warmer summer months you’ll need to keep a close eye on your tanks temperature.
The second key requirement for keeping this fish in your home aquarium is the substrate you use. As they are bottom dwellers and like to burrow in the substrate and under rocks, you’ll need to use the right type of sand. If the sand is too fine it will make for an unstable burrow and could cause it to collapse and even topple the rocks onto your Blue Spotted Jawfish. A good mixture is around 75% coral sand, and 25% small pieces of reef rubble.
This will make the ideal substrate for them to build their new home safely. Also, ensure the sand is 3″ in depth minimum.
The Blue Dot Jawfish is known to be a jumper, so it is best kept in an aquarium with a tight-fitting lid to prevent escape.
If you provide a suitably sized tank, around 30 Gallons with the correct temperatures and substrate then there’s no reason why these fish won’t thrive within your nano reef tank.
It cannot be overemphasized how important the water temperature is. Keep the water temperatures cooler and they will be fine. Normal saltwater conditions of 71-76° F, pH 8.1-8.4, sg 1.020-1.025, KH 8-12 will be perfect.
Test your water weekly with a good quality test kit. We like the API Saltwater Test Kits available from Amazon.
In the wild, these fish mainly feed on zooplankton. Provide them with a varied diet of small meaty frozen foods such as plankton, vitamin-enriched brine shrimp, Mysis, and finely chopped krill, prawns, cockles and mussels. If you have a refugium then this will be very beneficial in providing a natural and welcomed food source.
This fish has to be classed as Moderate care level due to the cooler water temperatures but is still worth a look if you want a beautiful, interesting bottom dweller for your nano aquarium.

# 12 Pygmy Hawk
Scientific Name Plectranthias sp.
Family Serranidae
Temperament Semi-aggressive
Care Level Moderate
Diet Carnivore
Size 2"
Reef Safe With Caution
Tank Size 30 Gallons
Origin Cebu
Price $40
The Geometric Pygmy Hawkfish, Plectranthias sp., also known as the Geometric Pygmy Perchlet or the Hi Fin
Perchlet is a very sort after fish for nano reef enthusiasts. There are perfect for nano reef tanks and will not harm any corals, invertebrates or shrimps. Although there have been reports of them eating small shrimps so be careful if you’re adding smaller shrimps.
They are great reef dwellers in community tanks and only grow to around 2″ in size making them ideal for smaller nano tanks.
This Perchlet is actually a member of the anthias family, however, they do resembles a hawkfish hence the name.
They can be found in the wild in areas of rich coral growth and clear water (lagoons, channels or seaward reefs) at depths of up to 35-40 m. Found in the Indo-Pacific region, the Red Sea and the Eastern Pacific. This is a relatively new species to the saltwater aquatic trade and is in high demand. This hardy fish can be hard to come across in your local pet store or aquarium shop so if you see one, snap it up! Provide your Pygmy Hawkfish with a variety of marine meats, frozen preparations, and live feeder shrimp.
Bottom-dwelling invertebrates and zooplankton are also its favorite food.
It will sit on rocks and corals waiting for food to come by, sometimes they can be shy and often take themselves away behind a rock and hide for days at a time. This is nothing to worry about, every fish ( and humans ) needs some time away every now and then.
Provide plenty of rocks, ledges, and shelves for them to sit on and they will feel right at home.
# 11 Yellow Watchman Goby
Scientific Name Cryptocentrus cinctus
Family Gobiidae
Temperament Peaceful
Care Level Easy
Reef Safe Yes
Diet Carnivore
Size 4"
Tank Size 10+ Gallons
Price $20
If there are a couple of perfect relationships between different species of saltwater fish, shrimp and invertebrates like clownfish and anemones, cleaner wrasse and bigger fish then the yellow watchman goby and the pistol shrimp has to fit into that list somewhere.
In my opinion, if you own a Yellow Watchman Goby or you’re thinking of buy one then you must keep it with an Alpheus spp. pistol shrimp (e.g., Alpheus bellulus, the tiger pistol shrimp).
In this mutualistic symbiotic relationship, the pistol shrimp, who has very poor eyesight, continuously digs and builds the burrow while the goby stands guard against predators. Almost at all times, the shrimp keeps at least one of its antennae in contact with the goby so it can immediately sense when danger is near via the goby’s body language.
Native to the Western Pacific, where it can be found at depths of from 1 to 25 metres in coastal bays and lagoons.
The Yellow Watchman Goby has a torpedo-like body shape with two distinct dorsal fins and a rounded caudal fin.
They have the typical goby fused pelvic fins with high-set bulbous eyes and an oversized, “frowning” mouth. This is one of the main characteristics of the Watchman Goby. Who can resist that sad frowning face?
Growing to around 4″ maximum in size these fish make the perfect reef aquarium tank mates. Peaceful, interesting and relatively hardy they would always one of my first picks for any nano reef tank.
These fish are very peaceful but will become territorial and will fight with its own kind unless they are a mated pair.
It may try to jump out of the aquarium or other small openings, therefore, a tight-fitting lid is required to prevent escape.
Feeding these fish should prove no issue at all, in time they will accept most meaty foods and sometimes even dried flake foods that drop to the bottom of the tank. Provide them with a healthy variety of foods such as mysis and brine shrimp, chopped clam or crustacean flesh, or frozen carnivore blends, at least twice daily and they will be just fine.
If you’re looking to at an interesting goby to add to your reef tank then we highly recommend these fish and with a pistol shrimp, you have a winning combination. Definitely in our top 15 nano reef tank fish list and probably always will be.
#10 Clownfish Scientific Name Amphiprion ocellaris
Family Pomacentridae
Diet Omnivore
Temperament Peaceful
Care Level Easy
Origin Most are now Captive Bred
Size 3"
Tank Size 20+ Gallons
Price $20
On the release of the film Finding Neno, this fish shot to the rankings of the most sort after saltwater fish for new fishkeepers. But even before the launch of this film, the Clownfish was already a favorite amongst aquarists due to there amazing personalities and close relationship with anemones.
For many years the common clownfish has been featured in most reef and nano aquariums but in recent years there have been many more varieties that have become available to the public like the Picasso Clownfish and Madagascar Clownfish. These fish are rare compared to the common clownfish and command a very high price.
These fish also have a grading system to judge the quality and price. One of the best places to find rare clownfish and learn how to grade them is Sea Reef Aquaculture. This company also breeds many new varieties so you have never had so many colors and varieties to choose from.
An amazing fact about these fish is that all anemonefish, including clownfish, are hermaphrodites. They are all born male and have the ability to turn themselves female when needed, but once the change is made, they can’t go back to being male. Sometimes the change is made when mating or when the lead female of the group dies.
Two males will become mates and the larger, dominant fish will become the female.
Most clownfish are now captive bred. The Captive-Bred Ocellaris Clownfish has other unique advantages over wild-harvested species. For one, the Captive-Bred Ocellaris Clownfish are hardy and more accustomed to conditions found in home aquariums. Therefore, it makes a great choice for beginners and experienced aquarists alike. The Captive-Bred Ocellaris Clownfish can also be kept with a variety of other captive-bred clownfish if introduced into the aquarium at the same time.