Blue Freshwater Fish – 7 Amazing Species7 mins read

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Blue freshwater fish
Image from Flickr

As a beginner or even more advanced aquarist, the thought of having Blue colored freshwater fish may have tickled your fancy, if so, it is quite fortunate that there are plenty of Freshwater fish species available in solid blue, or varied blue colors to choose from. The list compiled, according to extensive research, holds a variety of some of the most bold and exquisite colored Blue Freshwater aquarium species that may be of interest.

Freshwater Fish As An Aquarium Species

When referring to freshwater fish, especially those in the aquarium trade, it involves fish species that spend some or most of their lives in freshwater with a salinity of below 1.05%. There is however the exception of a few freshwater species that have a tolerance for more salinity and a preference for brackish water.

Freshwater fish are mostly found in Rivers, Lakes, and other freshwater bodies. According to sources 41.24 % of the fish species on earth are freshwater fish.

In the aquarium trade, there are freshwater fish that prefer cooler and warmer water conditions, which will most likely depend on the area that they are from and the climate there. There are amazing species of blue freshwater fish that can be considered.

Blue Color Variations In Freshwater Fish

As with other colored freshwater fish, blue freshwater fish, similarly, come in different shades of blue with different patterns and different hues. Here are a few of the many different types of blue freshwater fish colors that you can expect:

  • Dark Blue
  • Medium Blue
  • Pale Blue
  • Metallic Blue
  • Blue Pearl scale
  • Multiple Toned Blue
  • Powder Blue
  • Cobalt Blue
  • Diamond Blue

List Of Most Popular Blue Freshwater Fish Species

Finally, a few of the most interesting, popular, and even rarer Blue colored Freshwater fish that can be expected in the Aquarium trade. As can be noted, each species will be described in short detail, though it is well advised to do proper research before investing in a particular species.

1. Blue Betta Fish

Blue Betta Fish
Betta Fish also known as Siamese Fighters are traditionally from Thailand.

Likely one of the most majestic and popular Freshwater fish in the aquarium industry, with a feisty personality, and many color Variations. Betta Fish also known as Siamese Fighters are traditionally from Thailand. They are smaller, around 2.5 to 3 inches (6-8 cm) as adults, and have a lifespan average of 2-5 years in captivity.

  • Aquarium Requirements – Betta fish can be kept in groups of females; however single males must be kept. For a single male a 3 – 5 gallon tank is sufficient, though slightly larger for a group of four females. Bettas prefer water temperatures of between 24-28 ̊C, (75-82̊ F), and a water pH of around 7.0. They generally enjoy some swimming space, with a few hiding spots in their tanks, along with Live or synthetic plants, and indirect light.
  • Feeding – Bettas are mostly Carnivorous and enjoy flaked or pellet foods especially marketed for Bettas, along with Live or Frozen meat-based foods such as Blood Worms, Brine Shrimp, and Daphnia. They can be fed a small pinch of food twice a day.
  • Temperament – “Siamese Fighters” should give a clue as to their aggression, towards their species. Females form a hierarchy with an alpha female and thus should be kept in groups of at least 4. Males will fight each other to the death. Generally, Bettas will do well with most other peaceful fish species but may nip at the fins of slower fish.
  • Breeding – Though tricky to breed in captivity you will need a separate breeding tank in which the female must be introduced first before the male is added to a compartment. If they accept each other, they will spawn. They are cannibalistic and will eat their eggs and young, thus, both parents must be removed from the breeding tank after spawning.
  • Color Variations – Bettas in general come in so many color variations and similarly different tail and finnage variations. The Blue Betta will either be a deep dark blue, medium blue, light blue, or metallic blue color. Similarly, there are multiple-toned colors with blue.

2. Blue Guppy

Blue Guppy
A tank of between 10 – 20 gallons will be suitable for a group of Guppies. Image from Flickr

Though they might sound quite common, there is nothing common about the Guppy, especially Fancy Guppies. They are extremely popular aquarium fish that enjoy fresh to slightly brackish water conditions, are very tolerant in terms of water parameters, and are easy to keep. Guppy Males are the most extravagant in colors, compared to larger and more dull females. They are small, around 1.5 — 3.5cm (0.6 – 1.4 Inches) in males, and 3–6 cm (1.2 — 2.4 Inches) in females, with a lifespan of 1-3 years, and 5 years as the maximum recorded age. Essentially from Northeast South America Guppies can be found all over the world today, especially in the Aquarium trade, luckily, They come in many blue variations that are quite enticing.

  • Aquarium Requirements – Guppies should always be kept in groups with a ratio of two females per male at least, as they are shoaling fish. A tank of between 10 – 20 gallons will be suitable for a group of Guppies. They prefer water temperatures of between 78–82°F (25.5–27.8°C), and a pH 6.5 to 8.5. You can add a small amount of salt to their aquarium as they enjoy slightly more brackish water conditions.
  • Feeding – Guppies are generally Omnivores and should be fed a varied diet of quality pellets or flakes, vegetables, and meat-based foods including brine shrimp and bloodworms.
  • Temperament – They are a popular aquarium fish for both their peaceful nature and exquisite colors. Guppies are shoaling and should be kept in groups, as they need to socialize with their species.
  • Breeding – According to breeders and trusted sources Guppies are well known for their enthusiasm when it comes to breeding. They will breed in any aquarium set-up. They are Live-bearing, giving live birth to their young rather than laying eggs. However, parents may eat their eggs and young and show no parental qualities. Therefore in a well-planted or separate tank, the young fry have a better chance at survival.
  • Color Variations – The Blue Guppy ranges in colors such as Light or dark blue, electric blue, neon blue, or Japanese blue variation with either just the tail or the tail and body exhibiting blue coloration. Guppies similarly have a few different tail shapes depending on the species.

3. Blue Peacock Cichlid

Blue Peacock Cichlid
The Blue Peacock Cichlid, or Aulonocarae is a genus belonging to the haplochromine Cichlid family, naturally found in Malawi and East Africa inhabiting lakes. Image from Flickr

The Blue Peacock Cichlid, or Aulonocarae is a genus belonging to the haplochromine Cichlid family, naturally found in Malawi and east Africa inhabiting lakes. They are different from the more aggressive Mbuna Cichlid species, being non-aggressive, and thriving in warmer water conditions. Blue Peacock Cichlids are around 10.2-12.7cm (4-5″) in size when adults, known as medium-sized aquarium fish, with an average lifespan of between 5 and 8 years.

  • Aquarium Requirements – It is preferred to keep them in a ratio of two females per male, and a 75-gallon tank. They enjoy water temperatures of between 25 -28 °C (77-82.4°F), with a 7.5 to 8.0 pH. Generally, their aquarium set-up should consist mostly of rocks with a sandy substrate, and well-oxygenated water, they are not particularly fond of many plants.
  • Feeding – Keep in Mind these Cichlids are prone to and thus must be fed with care. Only feed them twice a day, and enough for them to finish in a few minutes. They are Omnivores and enjoy meat-based foods such as chopped brine shrimp and blood worms, as well as fresh balanced vegetables, along with a staple of pellet or flake foods.
  • Temperament – In Comparison to other Cichlid species they are relatively peaceful though should be kept with more robust tank mates. Males will generally be more territorial toward each other
  • Breeding – Peacock Cichlids in general are a joy to breed, and the female has superb maternal instincts. All you need is a separate breeding tank with a male and female that will spawn. The female will care for the eggs and young fry until they are more independent.
  • Color Variations – The Alulonocara family Cichlid is known for its pointed anal, dorsal, and ventral fins. The species is generally yellow with blue around the head, along its tail, and with blue fins. The anal fin may be yellow with blue spots and bands. There are many Peacock Cichlid species, though the Blue Peacock Cichlid predominantly has blue, and sometimes a few orange spots. The males are generally much more colorful than the females.

4. Blue Opaline Gourami

Blue Opaline Gourami
The Opaline Gourami Trichopodus Trichopterus, as scientifically known is native to Southeastern Asia and available in a blue or gold color variation. Image from Flickr

The Opaline Gourami Trichopodus Trichopterus, as scientifically known is native to Southeastern Asia and available in a blue or gold color variation. It is a medium-sized freshwater fish species ranging in size from around 15 cm (5.9 inches) as an adult.

  • Aquarium Requirements – The Blue Opaline Gourami requires a more spacious tank of around 20 gallons per fish with temperatures of around 22 -28 °C (71.6-82.4°F) and a pH of between 6.0 and 8.0. Gouramis in general enjoy open spaces for swimming with tall plants as hiding spots, and a strong current from their filters.
  • Feeding – Gouramis are omnivores requiring a more balanced diet, including quality flakes or pellets. They enjoy proteins such as brine shrimp, daphnia, bloodworms, and blanched green vegetables as a treat. You can feed your Gourami twice a day.
  • Temperament – Opaline Gouramis are robust, peaceful, and not prone to fin nipping, they can easily be kept with the most peaceful freshwater fish species. Males may be slightly territorial towards each other. Unfortunately, Opaline Gouramis cannot be housed with other aggressive Gourami species.
  • Breeding – males will build a bubble nest for the female to lay her eggs. After spawning the female should be removed, or the male will chase her away and take on the responsibility of parenting.
  • Color Variations – The Opaline Gourami is available in a blue or gold color variation. They have vivid black spots on the sides of their bodies that may fade as they get older.

5. Blue Discus

Blue Discus
For the Blue Discus a large 55 to 75-gallon tank is required, and they need to be kept in a group of four or more.

The Discus (Symphysodon) forms part of the Cichlid species that originates from South America. It is a more peaceful and placid Cichlid that is known for its remarkable colors, patterns, and intriguing behavior. It may be found that some Discus variations are quite rare and that they are generally a more sizable and expensive fish species, for knowledgeable aquarists.  The Discus has a lifespan of around 10-15 years and an adult Discus can grow up to 10 Inches (25 cm) in size.

  • Aquarium Requirements – For the Blue Discus a large 55 to 75-gallon tank is required, and they need to be kept in a group of four or more. Water with a low current, that is crisp and clean, with temperatures around 26 to 30°C (80° and 86° F), and a pH of 6.0 to 7.5 is preferred. A large tank of between 55 – and 75 gallons will be required for a group of four or more Discus fishes. The Discus in general prefers a natural environment with sandy substrate, rocks, and a few live plants, along with plenty of open space for swimming.
  • Feeding – Known as an omnivore, quality Discus-specific flakes or pellets are required, along with algae rounds, and live or frozen foods such as Bloodworms, insect larvae, and brine shrimp.
  • Temperament – An elegant and striking fish species, the Blue Discus similarly has a social and peaceful nature, with rare reports of aggression.
  • Breeding – If kept in groups with males and females, they will pair off to spawn claiming a territory. Discus parents are nurturing and will care for their own young.
  • Color Variations – The Blue Discus comes in quite a few shades with many shapes and patterns, along with different colored lines more information on Discus color variations can be found in the Discus Catalog.

6. Blue Zebra Cichlid

Blue Zebra Cichlid
The Zebra Blue Cichlid is a species from the Mbuna family of Cichlids native to Africa. Image from Flickr

The Zebra Blue Cichlid is a species from the Mbuna family of Cichlids native to Africa. It is a more aggressive Cichlid that is endemic to the lakes of Malawi. They can grow up to sizes of 8 Cm (3.1) inches and are medium freshwater aquarium fish with a 2–5-year lifespan.

  • Aquarium Requirements – A tank of at least 55 gallons is required for a group of four Zebra cichlids, whereas the ratio needs to be two males and three females. Warmer water temperatures of around 25.6-27.8°C (78 -82 °F) are ideal and a water pH of between 7.8 and 8.6. Similarly, they favor a clean tank with a few plants as hiding spots and open spaces for swimming. The sand substrate can be used, and rocks, caves, or Terracotta pots for hiding spaces.
  • Feeding – In the Wild Zebra Zebra Cichlids usually graze off the algae found on rocks and driftwood. They are herbivores requiring specialized pellets or flakes, algae wafers, and Spirulina supplements. You can treat them with occasional vegetables such as carrots, zucchini, and peas. In the wild, they graze on algae that they scrape off rock surfaces. They also feed on plankton that resides within the water column. It is necessary to duplicate their primarily herbivorous diet in captivity by feeding them food that is primarily vegetable-derived. A quality pellet or flake food is recommended, together with spirulina supplements. Regular treats of carrots, peas, and zucchini would also benefit them. Feed them at least twice a day. Be careful not to administer more food than can be consumed within 20 minutes.
  • Temperament – Unfortunately being from the Mbuna species Blue Zebra Cichlids are territorial and aggressive, not to be housed with other peaceful species, though contrarily can co-exist with similar aggressive species. They are notorious diggers and, thus, will enjoy a sandy substrate.
  • Breeding – The Zebra Cichlid is a mouthbrooder. The female will lay eggs on a rock, and pick them up in her mouth. She will continue to follow the male until he releases sperm into the eggs. The eggs remain in her mouth until they hatch.
  • Color Variations – The Blue Zebra Cichlid is a distinct color that is a pale blue with a few blue to black bars and orange spots on their anal fin. Mostly males are blue, and females yellow, however, they may have blue coloration with black and yellow bars. Other variations include the Red Zebra Cichlid, the Cobalt Blue, and the Lemon Yellow.

7. Cardinal Tetra

Cardinal Tetra
The Cardinal Tetra is slightly larger, at around 1.5 inches (3cm) as an adult, with a lifespan of around 2-5 years.

To end off, the small and peaceful Cardinal Tetra is a species many times confused with the more common Neon Tetra. It has more brilliant colors and originates from the Amazon. The Cardinal Tetra is slightly larger, at around 1.5 inches (3cm) as an adult, with a lifespan of around 2-5 years. More Information on the species can be found in their Care Guide.

  • Aquarium Requirements – Cardinal Tetras need to be kept in groups of 5-6 fish in a 20 – 30 gallon tank. They enjoy water temperatures of around 72-82̊ F(22-28̊ C) and a pH between 6.0 and 7.0. Cardinal Tetras in general enjoy a more heavily planted natural aquarium environment with sand or fine gravel substrate and a few hiding spots. An open space in the center creates an area for shoaling behavior.
  • Feeding – Known as omnivores a more varied diet is favored. Quality flaked foods and fresh proteins including smaller insects, baby brine shrimps, and blood worms are ideal, as well as vegetable treats that are shredded and blanched.
  • Temperament – The Cardinal Tetra like the Neon Tetra is quite hardy and easily kept by beginners. They have a rather bold temperament and prefer to shoal in groups, swimming in astonishing patterns.
  • Breeding – Cardinal Tetras need very specific water conditions to breed and thus must be separated from other fish species. They need a dimmer atmosphere with soft acidic water. After spawning males and females need to be removed from the breeding tanks, as they may eat their eggs or young.
  • Color Variations – The Cardinal Tetra possesses color like the Neon Tetra. It has a striking blue stripe running from the nose to the tail, and a red stripe just below the blue stripe. The belly is a soft white and the red colors will bleed into the transparent tail.

Final Thoughts

As can be seen, listed are some exquisite Blue Freshwater fish species varieties, each with their unique colors, and temperaments. It is vital however to ensure that you follow proper guidelines and care instructions, after proper research before choosing one of these species, as the list only touches on their main aspects and requirements to capture interest.

Frequently Asked Questions

What is the Rarest Blue Freshwater Fish Species?
The Devil's Hole Pupfish is known as the rarest, and most endangered Blue freshwater fish species only found in a water-filled cavern found in Nevada. The Petrochromis known as the Red Bulu Point is a Cichlid that is a very rare aquarium fish with some blue coloration on the fins.
What is the difference between the Blue Diamond and Cobalt Discus?
The Blue Diamond Discus has a more solid blue color, with a metallic hue, rather than the solid powdery blue hue of the cobalt.
Are Blue Freshwater Fish Species Rare?
The rarity will depend mostly on the specific species, though most solid-colored Freshwater fish are slightly rare, except for the well-known blue Betta fish.
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