10 Blue Freshwater Aquarium Fish

Disclosure: I may earn a commission when you purchase through my affiliate links. As an Amazon Associate I earn from qualifying purchases. – read more

Blue is a color that wil occur rarely in the wild, which is why we tend to appreciate it that much more. As a future aquarium owner, you probably want to build the most aesthetically-pleasing aquatic environment, as close as possible to a natural habitat.

One of the perks of crafting your own aquarium environment is controlling what fish you can use. Whether you’re going for a single-species tank or a mixed habitat, choosing your fish’s coloring is essential for creating a visually pleasing aquatic enclosure.

Today, we will discuss the 10 most exhilarating species of blue fish that will truly bring your aquarium to life.

1. Blue Guppy Fish

Guppies are tropical fish that have adapted to life in captivity better than any other species. They are fantastic breeders, capable of producing hundreds of guppy fry every month, and display an impressive variety of colors. Blue isn’t uncommon either, but certain varieties of blue are.

Guppies display an astounding diversity of colors and patterns, and the same stays true for blue guppies. Some of the most relevant blue guppies to consider include:

  • Moscow Blue Guppy – These guppies display diverse shades of blue, generally mixed with black, but only slightly. Most Moscow blue guppies actually lean more towards purple, and you can even find them in green variations. The Moscow Blue Guppy is the most expensive on the market, so expect to pay around $40 to $100 for one.
  • Electric Blue Guppy – Comes in dark and light blue with almost no pattern variation and a metallic shine. This species looks amazing in heavily planted tanks with natural or even artificial lighting.
  • Albino Blue Tail Guppy – This species displays a light-blue body that goes white towards the head, with white eyes. Only its dorsal fin and tail are clean blue, making for an interesting contrast.
  • Neon Blue Guppy – The Neon Blue Guppy showcases lighter shades, often mixed with rainbow colors and a neon nuance spread across its body. The Neon guppy is a great option for community tanks as its body will contrast heavily with other warmer colors.

General info:

  • Guppy females can store the male(s)’s sperm inside their body for up to a year and use it to produce offspring every month; this evolutionary feature is great for when females don’t get access to males for longer periods
  • Guppies can adapt to saltwater and freshwater, but they prefer to live in brackish water, since it better mimics their natural environment
  • Although they are not schooling fish, guppies still prefer to live in social groups, which keep them active and comfortable
  • Keeping guppies with large or aggressive tank mates can stress them out, which will lower their immune system and leave them prone to various diseases
  • The ideal temperature is between 72 F and 82 °F; colder waters will leave guppies lethargic and destroy their immune system while hot waters will contain less oxygen, which can lead to suffocation

2. Blue Betta Fish

There are few community tanks that don’t have at least a pair of Bettas. These are the most gracious and elegant aquarium fish you can find, thanks to their wide tails and fins.

The Blue Betta comes with a unique charm and different variations of blue, including dark and light shades in varying patterns. Some Bettas have dark blue heads with lighter bodies, while others have blue bodies with whitetails.

You can also find color mixes in blue Bettas, which can include shades of green, red, and orange if you’re interested in more color variation. Bettas are good for community tanks, although Betta males can get feisty and territorial towards each other.

General info:

  • Bettas are called Siamese Fighting Fish for their no-nonsense attitude; male Bettas fight for territory, food, and females more than other species
  • Bettas can life solo or in pairs and require at least 3 gallons of water per fish
  • A regular Betta fish can cost around $3-$5, but a blue variation can jump to $20-$50 or even more, depending where you’re getting it
  • Bettas will breathe to the water’s surface if their water has low oxygen levels; this is possible thanks to their labyrinth organ, allowing them to breathe atmospheric oxygen
  • If you’re going for a single-species tank, don’t keep more than one male in the environment unless the tank is large enough and has plenty of hiding spots

3. Neon Tetra

Neon tetras are small, energetic, and colorful and make for great additions to your community tank. Their small bodies display 2 dominant colors – red and neon blue. The blue comes in one solid stripe traversing the body from mouth to tail laterally. The red comes in one solid patch that covers the rear portion of the abdomen and engulfs the tail.

Neon tetras grow up to 1.5 inches and live around 5 years in optimal conditions. Neon tetras are calm and docile as a shoaling species and do well in groups of 10-12 members minimum. They also resort to schooling behavior when scared or threatened.

You should never pair the Neon tetras with fish large enough to eat them because they will.

General info:

  • It’s rather difficult to differentiate between males and females; the only notable difference is that females have slightly bulkier abdomens
  • Breeding Neon tetras is a more complex task since they require ideal water conditions to reproduce successfully: temperature between 72 to 75 F, water hardness between 1 to 2 GH, pH up to 5.0 to 6.0, etc.
  • The tetra fry are jumpy, so cover the breeding tank as soon as they are born

4. Electric Blue Ram

The Electric Blue Ram is a Cichlid and a perfect option if you’re looking for docile, adaptable, and calm fish. They can integrate within any fish community so long as their tank mates share their friendliness. The Blue Ram displays several base colors like blue, gold, and orange.

The blue ones also display metallic nuances, making them sparkle in the light. They are omnivores and can grow up to 2-3 inches, depending on their environmental conditions, diet, and gender.

General info:

  • Blue Rams are excellent breeders as they tend to produce offspring every several weeks, given optimal living conditions
  • The Blue Ram is generally a peaceful fish displaying low territoriality and food competition; they will, however, become aggressive during the mating phase
  • Blue Rams require higher water temperature than other Cichlids, between 80 °F to 85 °F
  • This species is rather sensitive to fluctuating water parameters, especially temperature
  • Blue Rams are omnivores and may sometimes be picky eaters, refusing dry foods

5. Electric Blue Hap

If you’re a fan of predator fish, the Electric Blue Hap is the next best thing. The fish’s appearance speaks volumes about its biological and behavioral orientation. The long, thick body displays a well-developed dorsal fin, covering the entire spine from nape to tail.

The Blue Hap showcases a prolonged head with a wide mouth, a trapezoidal caudal fin, and wide eyes that are either brown, black, or dark blue.

As part of the Cichlid family, the Blue Hap doesn’t go too well with small or timid fish. It’s not particularly aggressive, but its predatorial nature often gets the best of him. The fish can grow up to 8-10 inches, with males being larger and more colorful than the females.

With a life expectancy of up to 10 years, this fish is ideal for single-species tanks primarily.

General info:

  • The Electric Blue Hap does well in groups of 3-4 individuals, necessarily consisting of 1 male and 2-3 females
  • A group of 4 Blue Haps require at least 80 gallons of water; if you have 2 males in the same tank, you need at least 100 gallons and a lot of decorations and plants to extra hiding spots
  • Although the Blue Hap is rather peaceful in general, it will attack and eat any fish that can fit into its mouth
  • The ideal water temperature rests at 75-82 °F
  • Blue Haps have voracious appetites, so you should provide them with a fasting day per week to prevent overfeeding-related health issues

6. Blue Dolphin Cichlid

If you’re after a more exotic blue fish, the Dolphin Cichlid is your best bet. This bulky Cichlid displays a heavy body with a prominent forehead and thick lips. The fish will also come in light blue nuances with little color variation throughout the body, while the head is often dark grey.

Size-wise, Dolphin Cichlids can reach around 20 to 25 inches in size, with some species being larger than others. This is a carnivore, so you can’t really match it up with smaller fish species.

Dolphin Cichlids are best kept in single-species tanks, especially since they require a lot of space to feel comfortable. One Dolphin Cichlid may need around 100 to 125 gallons of water to remain healthy and active in the long run.

General info:

  • Dolphin Cichlids are rather peaceful, but males can get aggressive at times due to territorial behavior and solidifying their hierarchy
  • Provide Dolphin Cichlids with a thick, sandy substrate since they love to dig into the dirt
  • This species doesn’t need aquatic plants for decorations since they will typically break them apart or unearth their roots
  • The ideal water conditions revolve around 72 to 84 °F, a pH between 7.0 and 8.8, and water hardness between 10 to 18 DH
  • The Dolphin Cichlid’s diet should be protein-based, consisting of worms, shellfish, and various other live food options

7. Coral Blue Dwarf Gourami

The Blue Dwarf Gourami comes in 2 dominant color variations: neon and powder blue. They grow up to 3 inches and never display clean colors. Most Gourami fish showcase striped patterns, mixing their blue nuances with green or red stripes and spots. They have stock bodies with identical dorsal and abdominal fins covering more than half of their bodies.

Despite the fish’s relatively small size, the Blue Gourami requires at least 15 gallons of water for itself. This makes it difficult to keep it in community tanks, but not impossible, so long as you provide the fish with a heavy-planted habitat.

Just don’t house them with flashy or energetic fish since male Gouramis may see them as competition and become aggressive.

General info:

  • The Blue Dwarf Gourami needs to live in aquariums with at least 50% of the space occupied by plants
  • The Dwarf Gourami possesses a labyrinth organ, just like the Betta; this organ allows the fish to breathe atmospheric air since it cannot get enough oxygen from the water
  • The Gourami displays 2 long, and thin antennae-like appendices below its abdomen, used for navigating the environment and looking for food
  • Some compatible tank mates for the Dwarf Gourami include the neon tetra, gold and cherry barbs, and various species of Rasboras

8. Lake Kutubu Rainbowfish

The Lake Kutuhu Rainbowfish (the turquoise rainbowfish) can grow up to 5 inches, but it will remain generally smaller in captivity. It has a varying body shape, ranging from long to stocky, with a pointy head and a trapezoidal caudal fin. Its dorsal and abdominal fins are smaller, growing from the fish’s mid-section to its tail.

The fish’s base color is blue with iridescent variations, providing the Kutuhu with rainbow colors under bright light. This is an omnivorous and peaceful species but can exhibit high levels of energy translating to a more jittery behavior. This means that Kutuhu’s presence may scare off more laid-back and slow-moving species.

General info:

  • Lake Kutuhu does well in groups of at least 6 to 8 members since it displays shoaling behavior
  • This fish ranks as a cold-water species, as it prefers temperatures between 66 °F and 77 °F
  • The fish will eat mostly anything, including live, dried, and frozen fish food
  • Keeping several males together will boost their coloring but increase their aggression towards one another as well; find the balance point and provide them with a lot of plants to minimize aggression

9. Blue Discus Fish

The Blue Discuss fish comes with disk-shaped body, short tail, and large and round dorsal and abdominal fins. This blue variation displays an incredible variety of color patterns, from spotted blue with red and green shades, to dark blue with black stripes and red fins. The Blue Discuss fish can grow up to 8-8.5 inches and requires a lot of space to feel comfortable.

This fish species is more demanding in terms of care and maintenance, which is why I don’t recommend it to beginners or even intermediates. You should keep the fish in groups, but you can also introduce it to community tanks with other peaceful and friendly species.

  • General info:
  • The Blue Discuss fish requires warmer waters with temperatures between 78 to 86 °F
  • This species requires more complex care, regular water changes, and 0 ammonia and nitrites to remain healthy, making it unsuitable for inexperienced fish keepers
  • Keep the fish in schools of 6-8 individuals, since they are family fish, used to bond with each other
  • Unlike many aquarium fish, the Blue Discus female will care for the young, feeding them with mucus until they become independent

10. Blue Acara Cichlid

The Blue Acara Cichlid is similar in appearance to the Electric Blue Hap, although it doesn’t display the same predatorial, mean appearance. This Cichlid has a long body with a trapezoidal caudal fin and a dorsal fin covering its entire spine. It comes in several blue variations, often with metallic glows and green or purple nuances.

This species can grow up to 6-7 inches and requires around 30 gallons of water to thrive and remain comfortable over the years. It’s an easy-going fish and rather well-behaved compared to many other Cichlids. The Blue Acara can live up to 10 years in captivity with proper care and adequate maintenance.

General info:

  • The Blue Acara is adaptable and hardy and doesn’t face too many health issues, given optimal water conditions
  • The species is omnivorous but typically requires more protein than other species
  • The Blue Acara fares the best with members of its own species and should live in groups of 6 to 8 at minimum


If you love bluefish, this list provides you with great options for your community tank. Just be wary of the fact that not all species are compatible with each other. Learn as much as you can about your preferred fish species to avoid incompatible mix-ups, which may cause problems in the long run.

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.
Leave a Comment

Your email address will not be published. Required fields are marked *