Nature is an amazing force, driving a trillion types of speciation, creating all sorts of creatures.
Fish are no exception.
There are millions of different species of fish, each with their own unique coloration and patterns. Some of the most beautiful species on earth can even be kept in your own home aquarium.
25 Beautiful Fish That You Can Keep in an Aquarium
Here are our top 25 pick for the most beautiful fish in the world (that you can keep in an aquarium):
Goldfish are normally underestimated in terms of size and beauty, as the average person only sees the baby common goldfish sold at fairs. Most never imagine that these little fish turn into huge 10-12” fish that dance and glide underneath the water.
Of course, this only applies to the common goldfish. There are quite a few varieties of goldfish, along with many different patterns and colorations.
For example, those koi lovers out there who can’t deal with a 3- or 4-foot-long fish can get shubunkin goldfish instead. These are goldfish that typically have long fins and come in many different color patterns that mimic koi, such as the sky blue shubunkin.
There are also fantail, jikin, watonai, wakin, oranda, lionhead, ranchu, ryukin, shubunkin, comet, bubble-eye, celestial eye, demekin, butterfly, telescope, pearlscale, veiltail, black moor, tosakin, pompom, shukin, and nymph varieties.
Koi are famous for their elegant patterns and form, but most people don’t have the space to create their own beautiful koi pond. Most koi grow to an average of two feet, though three or four feet in length is not unheard of.
While these won’t technically fit in your aquarium long term, indoor ponds are still an option for keeping them. They are truly magnificent fish, and if given the option, you should keep them at least once.
Guppies are underrated in terms of beauty, as most people only see the ones in chain stores. There are hundreds of guppy varieties, meaning there are always varieties that will fit the color scheme of your tank.
Guppies are very hardy fish and love hard water, making them easy to keep for most people. However, the fancier the strain, the weaker they are. For guppies, a 10-gallon tank is a good starting point for a trio (one male, two females).
They come in too many varieties to list here, but there truly is a strain for everyone. If you like a lot of patterning and bold colors, look into mosaic guppies. If you instead prefer solid or calmer coloration, investigate the albino strains, some of which still have striking color.
22. Betta fish
Betta fish, or Siamese fighting fish, are also underestimated in terms of color. Just like the guppies, there are a great number of tail types, color patterns, sizes, and even species.
Most people only know about the common domesticated betta, but there are wild bettas with gorgeous patterns.
For example, Betta brownorum is a rust red little fish with a beautiful light blue iridescent patch of scales in the middle of its body. Each species of betta has a unique color pattern, size, and shape.
Most bettas are also easy to care for, requiring only a 5- or 10-gallon minimum tank size, depending on the species.
21. Boesemani Rainbowfish
If you love schooling fish and are looking for something unique, the Boesemani Rainbowfish may be just the thing for you.
These are some of the most vibrant and colorful schooling fish out there and really bring that something extra to your tank.
They are rather large, getting about four inches, so a four-foot tank should be the minimum size for their school. In a planted tank, their coloration really pops. People will definitely ask you about these colorful little guys.
20. Freshwater Angelfish
Beginner aquarists may be unaware that there are freshwater angelfish, but these fish have been domesticated for almost 100 years. There are hundreds of color and pattern types, and even different scale and types.
The most common type seen in stores are the Koi, Zebra, and Silver angelfish. These fish do best in aquariums 40 gallons or larger, and while they may do well in a community setting, they can turn aggressive and eat smaller fish and invertebrates.
Freshwater angelfish are not picky eaters and are easy to care for. They are normally used as a centerpiece fish for a community aquarium because of their large size and striking coloration. Just like guppies, there is truly a variant for everyone, and you can even choose between pearl scales and normal scaled angelfish.
19. Clown killifish
Killifish are often overlooked in the aquarium trade due to the short lifespans of annuals, but there are many gorgeous species that have decent lifespans. One of the most attractive species is the clown killifish.
This tiny fish scarcely grows over 1.5” and only need a 10-gallon tank. While their bodies have only brown and yellow stripes, their tails look like ornate fans. They have a wonderful symmetry of blue, red and orange on their famous tail fins.
18. Ram Cichlid
This little cichlid is one of the only cichlids that is fit for a 10-gallon aquarium, though a 20 is better. They are extremely easy to care for and breed, though there are some more sensitive strains, namely the Black German Ram.
Despite the variety of morphs, the normal Ram Cichlid is absolutely stunning. The most common color morphs are the common, electric blue, gold, black and longfin. These little fish are great for community tanks, and while territorial, get along with peaceful tankmates.
They are also one of the cheaper fishes on this list, both to care for and to purchase. Rams are normally only $5-10, which is a great price for such a gorgeous and interactive fish.
17. Blue Gularis Killifish
The Blue Gularis is another gorgeous killifish. These fish also have long and flowing fins, unlike the clown killifish. They have wonderful mottled and striped pattern on their body.
They do vary in color quite a bit, but most have bodies ranging from pale tan to blue with a red or pale pink patterning. Their fins have vibrant blue, yellow, orange, and green coloration, with bold stripes throughout.
This is one of the larger killifish species, with specimen reaching sizes between five and six inches. Due to their size, they need at least a 20-long tank, though a 40 breeder is better. These tanks have long dimensions that provide adequate horizontal swimming space.
16. Discus Fish
This species of cichlid was previously one of the holy grails of fish keeping, as the wild caught Amazonian fish were incredibly sensitive. However, these have now been in the hobby long enough to be kept by intermediate aquarists, not just expert ones.
The Discus has also been bred into many different color morphs and patterns, creating incredibly vibrant fish. Their form is rather unique, as they look as flat as a flounder, but swim upright like most other fish.
While they have become much hardier, they still need a great deal of care. Because they are carnivorous, they need to eat rich foods like beef heart, meaning changing the water often is essential. Sometimes as often as every day, but this usually only applies to juveniles.
15. Flowerhorn Cichlid
These cichlids are seldom seen in chain pet stores despite their ease of care and boisterous personalities. These hybrids are the ultimate “pet” fish, as they were created to be as personable as possible.
Depending on the type, of which there are many (check out our Flowerhorn Care Guide), the minimum tank size varies. A 75 or 125 gallon is the largest you’ll need for one fish.
The larger types of flowerhorns reach 14” while smaller types max out around 6”. Most Flowerhorn owners keep their fish in bare tanks, as this encourages them to interact with their owner.
While these cichlids are aggressive towards most other fish, they display a great deal of fondness to their owners. Some of them even enjoy being petted!
The dragon fish has long since been held as an important and regal figure, as well as a protector. Legends of owners having near death experiences and coming home to find their fish dead has led to the belief that this fish will meet death in exchange for its owner’s life. It will also take on the sickness of the owner.
Of course, this is simply legend, but the beauty of the fish is a truly legendary. The Asian Arowana, while being the most beautiful and vibrant, is illegal in the United States. Luckily, there are several other types of arowana available, such as the Jardini, Silver, Black, Blue, and Nile Arowanas.
These, like Discus, need a high protein and rich diet, meaning they too produce a great deal of waste. In addition, they get absolutely massive. Just like Koi, they can reach 3-4 feet in length, so custom tanks are often required to hold these beasts.
13. Peacock Gudgeon
The peacock gudgeon is a wonderful addition to nano tanks. They have striking iridescent patterns across their body and fins that shine just perfectly in a planted tank.
They can be kept together in groups, which is fantastic to see, and only need a 15- or 20-gallon tank. They get along very well with other fish, so tank mates are not often an issue.
Peacock Gudgeons swim around in the upper, mid, and bottom levels of the aquarium, but they love to hang out in little caves. They greatly appreciate any caves you can give them, and males will establish territories based around the caves.
12. Firefish Goby
While these guys are a common saltwater choice, it doesn’t take away from their beauty. After all, their brilliant coloration is part of the reason for their popularity.
They only get about 2 or 3 inches, so they can thrive in a 20-gallon tank. They are coral and invertebrate safe (well, not the teeny tiny ones, but the ones you buy will be safe).
They are rather shy, but also full of personality. As long as they don’t have predatory tank mates, the lighting is not excessive, and they have a cave or two to hide in, they are easy to care for.
11. Designer Clownfish
Designer clownfish are relatively new. These are simply Ocellaris Clownfish (pictured above) that have been selectively bred into over fifty different colors and patterns.
These little dudes are great for starting out your saltwater obsession. A 20-gallon tank is a great size to start out with for a clownfish. They are compatible with a great number of other fish and aren’t as shy as the Firefish goby.
Normally, these are available for sale around the size of an inch, but they reach three or four times that size. They also appreciate having a good deal of cover, especially if a host anemone or coral is not available.
These fish need very large tanks, around 125 gallons. They are carnivorous, extremely opportunistic, and reach over a foot in length, so tank mates must be chosen with extreme caution.
Despite their large tank requirements, they are a hardy fish and relatively easy to care for. They can be trained to take frozen krill and fish, which makes feeding simple.
Once you see the elegant way in which their fins ripple while they drift around, you will want one of your own. It is not only their patterning that makes this fish so gorgeous, but also the way in which they move.
9. Marine Betta
Now, before you start thinking that we listed the same fish twice, the Betta splendens and Marine Betta are extremely different species. This galaxy speckled fish is also called the Comet and has some truly unique behavior associated with its patterning.
As you can see, it has a large “eye” spot on the dorsal fin. These fish like to hang out in dim areas and crevices and stick only their tail out of an opening to mimic a moray eel. In addition, they will approach their prey sideways, so when the prey tries to get away from the “eye” and perceived head of the fish, they swim towards the actual mouth instead.
They will eat smaller fish and invertebrates but are normally reef safe. The marine betta can be a picky eater, though many have had success with California blackworms. In addition, they have a decent tank size for such a beautiful fish, requiring only a 55-gallon tank.
8. Queen Angelfish
While these pretty fish are breathtaking in both the juvenile and adult stages, their tank size requirement is an obstacle for many keepers. Their electric blue and jewel yellow coloration is unfortunately behind this barrier.
They need a tank of at least 250 gallons since they can get a foot and a half long, but it is possible to keep them in some community aquariums. They need a good mix of algae-based food and protein-based food, such as frozen Mysis shrimp.
7. Regal Angelfish
These angelfish are absolutely beautiful, with striking white, blue, and yellow stripes. Most are wild caught, so they have a relatively long adjustment period, but can be easily trained to accept flake and frozen food.
Regal Angelfish require a tank of at least 100 gallons, as they can reach 10”, and prefer rocky reef set-ups. While they do prey upon some types of coral, this behavior can be reduced by making sure your angelfish is adequately fed.
These are peaceful fish and become extremely shy if kept with fish more aggressive than they are. Regal Angelfish are normally wild caught, however, some are caught using toxins and poisons, and these do not live as long. Try to ensure that the one you buy was not caught in this manner.
6. Flame Angelfish
These cute fish are relatively small for an angelfish, reaching a size of about four inches. Due to this, a 70-gallon tank is large enough to house them for their entire lives.
They exhibit a bright red coloration that is complemented by dark vertical stripes on the middle of their body. These fish are semi-aggressive and are not coral safe, but since they are small, they can still be kept with larger invertebrates, but no worms.
The best way to decrease aggression is to create many different caves and hiding places across the tank. In addition, some people have had success with these fish and corals by keeping a large number of corals.
5. Annularis angelfish
While many angelfish lose most of their beauty as they grow out of the juvenile stage, this angelfish’s beauty is enhanced with age. While the juvenile fish have captivating and undulating stripes of various blues, the adults have a unique orange/tan body that makes their blue stripes glow.
These angelfish reach about a foot in size and require aquariums of at least 220 gallons. There are several captive bred specimens and color variations available.
They can become territorial once introduced to a tank, so it is best to introduce them last to a community aquarium. In addition, they are not considered safe for reefs or sessile invertebrates.
4. Lagoon Triggerfish
The Lagoon Triggerfish is one of the most striking triggerfish available. They have a light gray or tan body with an array of gray, blue, green, and black stripes across. Despite the fact that they grow to 10”, they are relatively simple to care for.
They need a tank of at least 180 gallons and cannot be kept in a reef tank. These fish tend to be a little destructive to the tank, rearranging decorations and live rocks however they want, or just knocking them over.
Just like pufferfish, a triggerfish’s teeth never stop growing, so they need a steady diet of high protein, shelled creatures. Clams are essential to keep their teeth down, but they should also be fed fish, squid, krill, and shrimp.
3. Crosshatch Triggerfish
The crosshatch triggerfish has a striking golden body with a brown face crossed sapphire stripes. The scales are rimmed with black, giving a crosshatch appearance. They reach 11” in size and need a 180-gallon aquarium.
If the fish is a male, the dorsal and anal fins are be ringed yellow, with a red and pink rimmed tail fin. On the other hand, females have red ringed anal and dorsal fins with a yellow bordered tailfin. For both sexes, the interior of the fins are gray.
The behavior and diet of this fish is essentially the same as the Lagoon Triggerfish, as this fish also needs meaty foods and will knock over rocks. Even though they can be a tad destructive, they still need their rocks and decorations to feel secure.
2. Clown Triggerfish
The clown triggerfish is unique due to the dynamic differences in its color and pattern. While the other gorgeous fish have a great variety of coloration and mosaic patterns, this fish has vibrant white and yellow spotting on a black body.
This triggerfish is no exception to the boisterous and mischievous nature of the other triggerfish. This fish will also knock over all the rocks and decorations, rearrange them to its liking, then repeat.
The feeding of hard and high protein food is also essential, as this fish is a carnivore with ever growing teeth. It does get larger than the aforementioned species, reaching over a foot and a half in length, so a tank of at least 300 gallons is required to keep this fish.
1. Mandarin Fish
Until we discover a new species, the mandarin fish will always be regarded as the most beautiful fish. Another name for this fish is the psychedelic goby, and for good reason, given the vibrant and hypnotizing allure of this fish.
There are several color types of this fish, though most rival one another in popularity and coloration (except the spotted mandarin fish). Unfortunately, these fish are incredibly difficult to care for, despite their small size of four inches.
The main issue with these guys is feeding. They normally eat only copepods, but in an aquarium environment, we simply cannot provide them with enough of their food source. Some have had luck feeding them newly hatched brine shrimp and California blackworms instead.
If you ever get the chance and capacity to keep one or more of these beauties, you most definitely should. As far as we know, there is nothing more gorgeous or captivating out there.
From the famous Freshwater Angelfish to the breathtaking Mandarin fish, our world’s oceans and lakes are filled thousands of colorful, beautiful fish
Even more amazing is that a lot of these fish can been kept in home aquariums.
While the list above is in no way complete (there are hundreds more amazing fish out there!), we hope you’ve enjoyed some of our top choices. If you feel like we missed any notable species, please send us an email with a few of your favorites!