25 Best Saltwater Aquarium Fish Species

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If you’re setting up a saltwater aquarium, consider yourself lucky because I’ll be handling the most difficult part – figuring out the ideal fish species for you. If you’re unsure what fish species fit which setup, I’m here to assist.

Today, we will discuss the 25 most popular saltwater fish species you’ll want for your aquatic setup.

Not all at one, of course, but some, depending on the layout, tank conditions, and your overall vision. So, let’s check them out!

1. Ocellaris Clownfish

The Ocellaris clownfish is one of many types of clownfish available. Other types include tomato, skunk, saddleback, maroon, cinnamon, etc. They all present variations in terms of coloring but not much else.

This is an omnivorous fish that grows up to 6 inches and can live around 20 years in captivity. These facts alone explain why the clownfish is so sought-after among aquarists.

Aim for a water temperature around 74-80 °F and at least 30 gallons of water for one fish. These are active animals that like to investigate and explore their habitat, so they need space.

More importantly, the clownfish is a rock and reef dweller. It requires hiding areas to help it feel safe and calm.

Difficulty of Care – Easy/Moderate

It doesn’t take much to keep your clownfish happy and healthy. So long as you provide it with a varied and healthy diet and keep water parameters stable, your clownfish will thrive.

The only problem worth mentioning relates to its tankmates. Clownfish tend to be more aggressive toward newcomers.

They will come around eventually but pay attention to the clownfish’s territorial tendencies whenever bringing a new fish into their environment.

And limit the number of clownfish males to prevent territorial struggles and violence.

2. Royal Gamma

You cannot craft a decent saltwater environment without adding at least a few gammas to the mix. This fish only grows up to 3 inches, but its presence makes up for its lack in size.

This colorful and energetic fish likes to dwell around underwater caves and reef structures where they feel safe.

You can quickly identify the royal gamma by its unique color pattern. The front half of the body is bright-purple while the lower half is a mix between orange and yellow. The fish also has a black line crossing its eyes.

The ideal water temperature revolves around 75-80 °F with a pH of 8.1-8.4. This carnivorous fish prefers protein-rich foods like seafood, brine shrimp, blackworms, etc.

Difficulty of Care – Easy

Royal gamma is a perfect fit for all aquarists, no matter their experience level. The idea is to help the fish feel safe and comfortable in its setting. Otherwise, it will simply stay in hiding and refuse to get out.

Add open-space fish since their presence will signal the royal gamma that the area is safe. Eventually, they will venture out more until they learn their habitat and adapt to their surroundings.

This is a friendly and docile species that will get along with a variety of other fish. They live in harems, so keep one male and at least 3-4 females per group. If you have 2 or more males, which is likely since there are no differences between the sexes, make sure there are enough females for everyone.

You will be able to distinguish the males during the mating season when they begin to fight for the females.

3. Yellow Tang

The yellow tang is your ideal cleaning fish since these are proficient algae grazers, keeping the tank clean and healthy.

They can live healthily for up to 10 years in captivity, although that duration triples in the wild. Yellow tangs are fairly large, reaching up to 8 inches from head to tail.

Their prominent snout speaks volumes about their favorite feeding method. They will spend most of aquatic their time grazing algae around their reef structures and other rocky setups in their habitat.

Provide them with a temperature around 72-82 °F and offer a varied herbivorous diet, and they will thrive.

Difficulty of Care – Easy/Moderate

The trickiest part is providing the fish with the ideal habitat setup. This is an open-space fish that also like to dwell around reef structures. So, you should find the right balance between the two.

Yellow tangs secrete a lot of skin mucus that’s designed to keep parasites away. This also allows them to swim faster since it lowers water friction.

So, they require at least 50 gallons per fish to meet their needs for regular physical activity.

Unfortunately, you can’t really keep more than one yellow tang per tank. Yellow tangs can be aggressive towards one another or even towards similarly-looking fish.

You can mitigate that aggression if you introduce both of your yellow tangs into the tank at once. This way, they will grow together and become more acceptant of each other.

Preferably, they should be of opposite sexes, since males won’t exactly be the best friends in the world.

4. Blue Tang

While blue tangs and yellow tangs are both surgeonfish and belong to the same family, don’t get it mistaken, these fish look nothing alike.

The blue tang grows way larger, up to 12 inches, has a torpedo-shaped body, and lacks the prominent snout of the yellow tang. The coloring is also next level.

Blue tangs display an astounding contrast of light and dark blue/purple with a yellow tail. It’s a unique and vibrant look, allowing the blue tang to stand out in a reef setup.

Keep the temperature around 73-82 °F and provide your blue tang with at least 100 gallons of water. This fish demands a lot of space, with some even going for 180 gallons.

Difficulty of Care – Moderate

I would say that the blue tang isn’t fit for beginners for a variety of reasons. One of them is the fact that blue tangs like to live in shoals. So, you’ll most likely need more than 1, hence the need for 180+ gallons of space.

The tank’s size alone will prove quite the challenge in terms of overall care and long-term maintenance.

However, you shouldn’t have too many problems as a more experienced aquarist. Blue tangs are relatively easy to care for, provided you ensure healthy waters, stable water parameters, and a varied and nutritious diet.

Don’t pair your blue tangs with aggressive fish species or other tangs. Blue tangs are rather timid in nature, so they will try to flee and hide in the face of danger.

They even play dead when threatened and will stress out if their tankmates are overly inquisitive or territorial.

5. Lyretail Anthias

This is a must, but one that’s bound to create a lot of logistical problems. Despite its name, the lyretail belongs to the Pseudanthias genus (pseudo = fake), hence, the name fake anthias. You may know this one by its more popular name, sea goldie.

This is a carnivorous fish that can grow up to 5-6 inches and demands a lot of swimming space.

The official recommendation is 125 gallons for a group of 5-6 fish, although you might need more than that. The ideal temperature sits at around 76-82 °F with a pH between 8.0 and 8.4.

The fish is easily recognizable thanks to its orange/red body and its long dorsal and caudal fins.

Difficulty of Care – High

This is clearly not for beginners. The lyretail is one of the more confusing fish species to keep due to its rather unique physiology.

All lyretails are born females and will change sex depending on social and environmental conditions. The males are almost double in size compared to the females.

The real problem is that lyretails demand a lot of space because they like to live in larger groups of at least 10 individuals.

So, it’s not uncommon for people to keep them in 150+ gallon tanks. Avoid this species altogether if you’re not experienced in handling such a water volume.

6. Tailspot Blenny

Tailspot blennies are small reef dwellers that grow up to 2.5 inches at most. They are hardy, shy, and don’t require much space to thrive. Around 8 gallons is sufficient for them because these fish tend to spend most of their time in hiding.

You will often see them lurking around the reef structures, caves, and crevices around their habitat.

Keep the water temperature around 7.5-8.0 F with a pH of 7.8 to 8.2.

These are effective algae grazers that will keep the tank clean and healthy. So, having multiple blennies is useful, provided you have the space and layout for them.

I recommend at least 20 gallons of water for 3-4 blennies, although more is better, especially since you’ll most likely have a variety of other fish.

Difficulty of Care – Easy

These diurnal algae grazers don’t need any special care. They are generally friendly, although newcomers may be a bit rattled at first until they figure out their role in the ecosystem.

Tailspot blennies also play dead when threatened, so don’t be in a hurry to remove your ‘dead’ blenny from the tank. Give in a couple of hours to make sure it’s not just acting.

The ideal tankmates should be small and non-aggressive or, at least, not interested in hunting other fish.

After all, blennies only grow up to 2.5 inches, which makes them easy prey for larger species.

7. Blue-Green Chromis

The blue-green Chromis is a reef damselfish that’s popular among aquarists thanks to its flashy coloring and vivid temperament. It will only grow up to 3 inches and will live around 8-12 years with proper care.

This omnivorous fish lives in schools of 4+ individuals, which is why it requires at least 30 gallons of swimming space. This is a handsome one, as blue-green Chromis displays a, well, blue-green coloring with iridescent margins.

An even more exhilarating fact is that the fish changes color when spawning, as males tend to take on a more orange nuance.

Difficulty of Care – Easy

So long as your chromis have sufficient swimming space and some good hiding areas, they won’t ask for much else. This fish is omnivorous, so it will consume a varied diet with both animal and plant-based nutrients.

One meal a day should suffice to prevent overfeeding and excess food residues.

Always pair your blue-green Chromis with peaceful and docile fish species to prevent bullying and fights. Chromis fish are sensitive to bullies, so they will retreat to safety when challenged.

Keep them in small schools of 4-5 specimens to help them feel safer and more comfortable in the long run.

8. Firefish Goby

The firefish goby is among the most unique entries on this list. This gorgeous specimen displays a bicolor body with pointy dorsal and ventral fins.

The fish only grows up to 3 inches and has a torpedo-shaped body, despite not being the most active swimmer you can find.

The lower part of the body is fiery red with brown margins, while the front half is light blue, almost transparent. The dark blue eyes create a beautiful contrast with the rest of the body.

This hardy fish prefers to live in stable water conditions with sufficient swimming space. You need around 30 gallons for one specimen, which should include the necessary space for your reef structures and rock formations.

Difficulty of Care – Easy

The firefish goby is easy to maintain, although it does come with some unique challenges along the way. This includes the fish’s territorial behavior towards other gobies.

You can’t really keep more than one firefish goby per tank because they’re bound to fight to the death.

You could try to keep a male and a female since they’re less likely to become violent towards each other, but nothing is certain.

Otherwise, the firefish goby is quite shy and timid and doesn’t fare well when paired with more aggressive fish species. They will either stay in hiding when bullied or try to jump out of the tank.

9. Coral Beauty Angelfish

The coral beauty angelfish makes for a fine addition to any reef-based environment. This fish grows up to 6 inches and demands at least 55 gallons of swimming space.

The ideal temperature for this species is 76-82 °F, along with clean and fresh waters.

This species is easy to identify, thanks to its unique color pattern. The coral beauty is a species of dwarf angelfish, although they have wildly different looks. Your typical coral beauty angelfish has a brown body with dark stripes and a blue head and tail.

The fish has an orange or red belly to complete the color contrast that makes this species so beloved among aquarists.

Some specimens also showcase neon-blue margins, especially around the tail, allowing the fish to glow in poor light conditions.

Difficulty of Care – Moderate/High

While this is a community fish that loves the presence of other tankmates, it is also quite territorial in nature. Males tend to fight relentlessly over space, food, females, if any, and hierarchical dominance.

The ideal aquatic setup should include a lot of rocks and reef structures to cut the line of sight between your angelfish.

Even so, I advise against keeping 2 coral beauty angelfish males in the same habitat. Instead, pair the fish with other species like tangs, damselfish, blennies, etc.

You most likely require at least 200 gallons if you plan on having more than 1 coral angelfish around.

10. Pajama Cardinalfish

If you’ve never seen a pajama cardinal, this one will take you by surprise. The fish is small, only growing up to 3 inches, but it makes up for it in coloring.

The cardinal comes with a yellow/green head and yellow or brown dorsal and ventral fins. A dark, thick, vertical line traverses the fish’s body in the middle area, separating the front and backside.

The fish’s back side is white with orange or brown spots. Hence, the ‘pajama’ addition to its name.

This is a carnivorous fish that demands at least 30 gallons of water and can live up to 5 years in captivity. It’s a fine addition to any peaceful community that thrives in stable and clean environments.

Keep the water temperature around 72-79 °F and ensure clean waters with stable parameters.

Difficulty of Care – Easy

This fish is easy to care for since it’s hardy, adaptable, and peaceful. It demands a lot of hiding areas due to its shy nature and because it’s a nocturnal animal.

So, it needs hiding spots to use during the day when resting.

These fish also require stronger water currents to mimic their natural conditions. Other than that, they are compatible with most peaceful fish species, including members of their own.

Males aren’t particularly aggressive towards each other except during mating and breeding, which is to be expected.

Despite them getting along well in most cases, always monitor their interactions to make sure they remain friendly.

11. Copperband Butterfly

Now we’re getting into a more demanding territory, as the copperband butterfly isn’t for the faint of heart. Don’t be deceived by the fish’s fluffy name since this is one mean creature.

The copperband butterfly grows up to 6 inches, is carnivorous, and displays high aggression towards members of the same species. And towards fin-rich fish that present them with ample opportunities for fin nipping.

This fish has a remarkable presence thanks to its purple and yellow body. The body shape reminds me of the yellow tang, including the elongated snout meant to collect live meals around rocks and reef crevices.

Aim for at least 75 gallons of water for this one and temperatures sitting at around 75 to 78 °F.

Difficulty of Care – High

This one is a poor choice for inexperienced aquarists due to its high water-quality demands. The copperband butterfly is more sensitive to ammonia, nitrites, and nitrates compared to other fish.

This makes this one prone to health issues like ich, marine velvet, lymphocystis, and uronema marinum, which is a ciliate parasite.

Not to mention, the fish will refuse to eat in subpar water conditions or when stressed or scared.

This only adds up to the overall difficulty of care, making the copperband butterfly more fitting for experienced aquarists.

12. Clown Goby

Clown gobies are what you can call décor fish. These fish are small, only growing up to 2 inches, and will fit perfectly in a lush reef environment.

They don’t need much space to thrive, which is why they’re great for both nano tanks and larger setups.

The water temperature should revolve around 72-78 °F with a pH of 8.1 to 8.4. Aim for a minimum tank size of 20 gallons, especially if you’re planning to have several clown gobies.

Diet-wise, these fish are easy to satisfy because they’re carnivorous and don’t eat much.

Difficulty of Care – Easy/Moderate

They are a good fit for beginners, except you need to learn more about them beforehand. These gobies will display territorial behavior when paired with other members of their own species.

It’s recommended to keep them in larger setups with a lot of hiding areas to minimize territorial fights.

Also, don’t pair your gobies with larger carnivorous fish that could attempt to eat them. Clown gobies produce a skin toxin meant to deter other fish from eating them.

Don’t worry, it won’t poison the tank water, but it might cause harm to any predator attempting to consume the goby.

Ensure a steady water flow because these fish like stronger currents.

13. Mandarin Dragonet

Mandarin dragonets are some of the most unique fish species you can get. These are bottom dwellers that spend most of their time lurking around the substrate.

Dragonets are on a constant search for food and will keep a low profile throughout the day.

Mandarin dragonets are highly colorful, with intense circle-based patterns spreading across their bodies. They will only grow up to 3 inches and can live up to 5 years in captivity.

You need at least 30 gallons for one fish, with 5-10 additional gallons for any extra dragonet coming into the mix.

Water temperature is best between 75 and 82 °F.

Difficulty of Care – Moderate/High

Mandarin dragonets typically rank as moderate in terms of care needs, but I would rank them at high. This is mostly due to their pretentious diets.

This fish is carnivorous and will spend most of its time looking for potential meals at the bottom of the tank. They prefer to consume copepods which you will need to grow specifically for them.

Most aquarists use live rocks in their tank for this purpose. So, you’ll need to mold the tank’s layout based on your dragonets’ food requirements. Fortunately, they aren’t as demanding in terms of water conditions.

Regular cleaning and weekly water changes are necessary, but at least the dragonet is hardy and resilient to diseases and parasites.

14. Naso Tang

Enough with the smaller species; this time, we’re discussing a true giant. Naso tangs grow up to 18 inches and come with a flat, oval-shaped body designed to draw all the attention.

You can tell that this is a tang by the shape of its head, with the small forehead dent specific to this species.

This fish lives 8 or more years in captivity and prefers water temperatures of around 75-79 °F.

The minimum tank size is 125 gallons for one specimen, as this is both a large and an active swimmer that likes to roam its territory constantly.

Difficulty of Care – High

I clearly don’t recommend the Naso tang to beginners for several reasons, such as:

  • The diet – Naso tangs prefer brown macroalgae over anything else. So, you need to get those specific algae for them. They will eventually accept other foods as well, like seaweed and veggies, but they need to graze since that’s their main feeding behavior.
  • Water conditions – They need a highly-oxygenated environment to remain healthy, active, and comfortable. You’ll need to invest in a good protein skimmer and several powerheads to keep oxygen levels up.
  • Naughty behavior and physical characteristics – These tangs are extremely aggressive towards other tangs and possess sharp spine fins near the tail. They can use these to slash or puncture other fish if threatened or stressed.

However, if you’re experienced in dealing with pretentious and aggressive tangs, this one is clearly for you. The Naso tang makes for an outstanding presence in your reef tank.

15. Pearlscale Butterflyfish

The pearlscale butterflyfish has a tang-like, shorter, and stockier body with a short snout. It’s usually light-grey in coloring with blue vertical stripes covering the mid-section and has an orange tail.

These fish grow up to 5 inches and demand around 30 gallons of water with plenty of hiding areas available.

They will also swim freely, but this butterflyfish is timider than other species, especially when first introduced to the tank.

Difficulty of Care – Easy/Moderate

This is a relatively easy-to-maintain species with moderate requirements in terms of water parameters. The pearlscale butterflyfish is also friendly and chill, allowing you to pair it with a variety of tankmates.

Hiding spots are necessary for the fish to retreat when stressed.

16. Flame Angelfish

The flame angelfish comes with the body composition typical to all dwarf angelfish. It has an oval body with rounded fins and a bulky composure. But it’s the coloring that stands out.

The flame angelfish displays a spicy mix of red and orange with black vertical stripes across the midsection. The tail comes with inflexions of iridescent blue for an even more breathtaking contrast.

This species grows up to 4 inches and can live up to 7-8 years in captivity. Go for an omnivorous diet and at least 30 gallons of space for one specimen.

Difficulty of Care – Easy/Moderate

This fish is a roamer. You will often see it swimming throughout the tank, often trespassing other fish’s territories.

However, they are calm and peaceful and will share space with a variety of other fish, provided they come with a similar demeanor.

You should ideally keep the angelfish in pairs or even in groups, so long as you limit the number of males.

Fortunately, the flame angelfish is easy to feed since it will accept most fish foods. It will also graze around the tank for brown algae, keeping the habitat clean and thriving.

This one is definitely a good pick for beginner and experienced aquarists alike.

17. Tomini Tang

Another day, another tang. This one grows up to 6 inches and comes with a brown or purple body with either orange or white fins.

The ideal temperature for the tomini tang rests around 75-80 °F since these fish enjoy warmer waters overall.

The problem is that this one is a highly active species. Tomini tangs are great at darting through their environment when hunting, playing, or simply patrolling their territory.

So, you need a lot of space, preferably 70 gallons for a pair. If you plan on having more than 2 tamini tangs, consider boosting your tank’s size above the 120-gallon mark.

Difficulty of Care – Moderate

The tomini tang isn’t too difficult to care for, but it can be tricky trying to find its place in a community setup. These fish are more aggressive towards newcomers.

To prevent this, always add your tomini tang last after you’ve already introduced the other fish.

When it comes to overall care requirements, consider the following:

  • Add seaweed and algae to their omnivorous diets since they’re among their favorites
  • Create the ideal conditions for them to graze around their habitat
  • Don’t keep more than 3-4 tangs in the same tank to prevent territorial or hierarchical fights
  • Partial water changes and regular maintenance are necessary to oxygenate and clean their habitat

18. Lawnmower Blenny

Every decent reef setup could benefit from the presence of proficient algae eaters. This is where the lawnmower blenny comes in.

This fish is great for grazing algae and keeping their habitat healthy and clean long-term.

Lawnmower blennies grow up to 5 inches and can live up to 4 years with optimal care.

You need at least 55 gallons to keep them active and engaging, especially since they will constantly roam their habitat when looking for algae to eat.

Difficulty of Care – Moderate

I didn’t rank this blenny as easy in terms of care requirements only due to its picky eating preferences.

Lawnmower blennies are notoriously difficult to satisfy if their habitat doesn’t contain sufficient algae or detritus. They are known to straight-up refuse food for days in such cases.

So, make sure that your blenny has a diverse, rocky environment where it can graze throughout the day. You can tell that the blenny is full and satisfied by its rounded belly.

Even so, I recommend supplementing their meals with supplements designed for herbivorous species for good measure.

19. Convict Tang

The convict tang is probably the less flashy surgeonfish in terms of coloring. All you get is a white background with black vertical stripes needed to justify the fish’s name.

This tang grows up to 8 inches and can live up to 7 years in captivity with optimal care. Be prepared to ensure a larger swimming space of close to 100 gallons.

Especially since this one is a group spawner, so you’ll need to have several of them in the same habitat.

The ideal temperature is 72-78 °F with pH values of 8.1 to 8.4, which is typical for saltwater fish. Stable and clean waters are necessary to keep the tang healthy and happy over the years.

Difficulty of Care – Moderate

Convict tangs rank as schooling fish. In other words, they live in groups and abide by specific hierarchical rules. This means that you need at least 100 gallons for 2 or more tangs, depending on their size.

Their habitat needs to come with a blend of open swimming space and plenty of hiding areas.

They can get grumpy and violent when paired with other tang types or fish similar in body composition and color.

You can outweigh these issues as a beginner aquarist with sufficient preparation and mindfulness. Just be ready for the challenge.

20. Pygmy Angelfish

Pygmy angelfish are truly astonishing fish in terms of coloring and color pattern. They have a yellow head with a bright-blue body with iridescent margins.

They also have blue circles around the eyes and rounded fins, providing them with a fuller look.

The pygmy angelfish can grow up to 3 inches and can live up to 5 years in optimal conditions. You may need to invest in a 55-gallon tank for this one since this angelfish is quite the active swimmer.

Keep in mind, that this is a coral nipper, especially when starving.

Difficulty of Care – Moderate

This is an angelfish, so you cannot expect it to be that easy to care for long-term. The males will display increased territorial aggression, so you should only have 1 per tank.

This alone will be a challenge, given that there are no distinct differences between males and females.

To minimize the risk of aggression between the pygmy angelfish and other tank occupants, ensure at least 100 gallons of space and offer multiple caves, rocks, driftwood, and other hiding areas.

Pay attention to the fish’s predisposition towards contracting marine ich or velvet, which are more prevalent in poorly-maintained setups.

21. Garibaldi Damselfish

The garibaldi damselfish sounds large and imposing, and that’s because it is. This species will grow up to 12 inches and demand a lot of space to thrive.

You may need to invest in a 100+ gallon tank which is only enough to fit one specimen.

The fish is plain orange with a bulky and strong body and round, compact fins. Garibaldi lives up to 25 years in captivity with proper care and requires a rocky set-up with plenty of caves and other hiding areas.

Difficulty of Care – Moderate/High

The main problem is that the garibaldi damselfish requires a lot of space for itself. The other problem is that this is an aggressive fish that cannot cohabitate with other members of its own species.

So, you can’t keep more than one per tank unless you have a 300-gallon setup.

These facts make the garibaldi unfit for novice aquarists, especially due to the need for a lot of space.

You can pair the garibaldi with other tankmates such as soapfish, tangs, large wrasses, lionfish, and others. Avoid smaller fish that your garibaldi could take for prey.

22. Foxface Rabbitfish

All rabbitfish share similar physical characteristics, so you probably have a good idea how this species looks like. The foxface rabbitfish comes with a long and oval-shaped yellow body with a black and white head.

The trademark prolonged snout is there, and so is the compact and clean overall look.

This species will grow up to 9 inches on average, which is decent, knowing that some rabbitfish can exceed 24 inches.

You need at least 75 gallons to help your foxface feel comfy and happy in its environment. The ideal water temperature is 72-78 °F.

Difficulty of Care – Easy

This is probably the best choice for a beginner aquarist, thanks to its undemanding requirements. The foxface rabbitfish is extremely resilient and hardy and won’t mind poorer water conditions should the situation arise.

Naturally, you still need to keep the fish’s habitat safe to prevent health issues along the way. But it’s good to know that your Foxface rabbitfish isn’t extra sensitive to ammonia and nitrites as other fish are.

This is a friendly and shy fish species that will get along with pretty much any other fish. The only thing to consider is the potential food-related incidents that may arrive along the way.

The foxface rabbitfish is an algae grazer, so avoid pairing them with other fish displaying similar feeding behavior to prevent competition.

23. Harlequin Tuskfish

The harlequin tuskfish ranks among the most colorful additions to any saltwater tank. These fish will grow to 10 inches and come with striped bodies displaying an array of colors like blue, orange, white, red, brown, purple, etc.

They also have large and blue frontal teeth and bulbous eyes, making up for a peculiar but interesting picture.

This species requires approximately 75 gallons for one specimen, although many aquarists go larger than that.

Since the harlequin tuskfish likes warmer waters, keep the water temperature around 77-82 °F. This one can live up to 7-8 years in captivity with proper care and when kept in a clean and stable environment.

Difficulty of Care – Easy

The harlequin tuskfish doesn’t need much to be happy. Provide it with sufficient swimming space, a nutritious and varied diet, and plenty of hiding spots since harlequins tend to be shier than other species.

When it comes to tankmates, don’t pair them with other harlequins due to their extensive territorial behavior. And don’t mix harlequins with shrimps or hermit crabs, since these are on their menu.

Any other peaceful and large fish species should do, provided everyone has sufficient room.

24. Lionfish

The lionfish is a staple in the aquarium business by now. This fish comes with a unique presence thanks to its colorful body, impressive size, and flashy spikes covering its spine and fins. Keep in mind that these spikes aren’t just for show.

The lionfish’s spikes are actually venomous, as the fish uses them in self-defense.

The lionfish can grow up to 12 inches or larger in some cases, which is why it requires at least 55 gallons of space. The ideal tank water temperature revolves around 74 to 82 °F.

Difficulty of Care – Moderate

The main problem is that the lionfish is a messy species. They produce a lot of waste and tend to eat a lot as well. You should only feed your lionfish once per day to prevent excessive accumulation of poop.

A good filtration system is necessary to keep the lionfish’s habitat clean and healthy.

Breeding them is almost impossible, as these fish are very pretentious about their water conditions during the mating season.

As a carnivorous, the lionfish will consume anything that fits its mouth. So, don’t pair it with small fish species that the lionfish could view as prey.

25. Threadfin Butterflyfish

The threadfin butterflyfish closes today’s list in style. This fish comes with an almost rectangular body and a prolonged, tang-like snout.

All threadfins display a similar color pattern: white background color with black stripes and yellow tails. They also have a thick black spot covering the eyes.

These fish can grow up to 8 inches, especially when they have sufficient room to manifest themselves properly. You need at least 150 gallons to properly accommodate your adult threadfin’s needs.

Difficulty of Care – Easy

This is an omnivorous and peaceful saltwater fish that will adapt to any aquatic community. It won’t bother other fish and doesn’t display any aggressive territorial behavior.

That being said, you should provide these fish with a lot of space and plenty of live rocks to munch on. They will spend their time grazing around their environment for algae and microorganisms around their habitat.

It’s a great pick for beginner aquarists, provided you’re courageous enough to take on a 150-gallon setup.


I’ve only detailed 25 of the most popular saltwater fish, but there are many more to consider. As a beginner, you should never skip your research day.

These fish are often extremely different in terms of setup requirements, diets, behavior, etc., so learn as many details as possible about your favorite species before getting it.

I hope that today’s list will help you in this sense!

Author Image Fabian
I’m Fabian, aquarium fish breeder and founder of this website. I’ve been keeping fish, since I was a kid. On this blog, I share a lot of information about the aquarium hobby and various fish species that I like. Please leave a comment if you have any question.
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