5 Most Popular Aquarium Fish

The guppy (Poecilia reticulata) is also referred to as millionfish and rainbow fish. It is now found all over the world and it is very popular among the aquarium fish keepers. It is a live-bearing fish under the Poeciliidae family of order Cyprinodontiformes. They can live many different environmental conditions.

Photo: Guppy Fish

Feeding guppy should combine vegetable and animal components. In wind condition, their food consists of algae, aquatic insects and its larvae. At present, these fish have several breeds. Their main differences are color, as well as the size and shape of fins and tails. Males are more intensely colored and their size ranges from 1.5–4.0 cm. Females are larger in size than male (2.5–7.0 cm), their belly is enlarged, the fins are reduced and their color is paler and resembles a grid. Guppy can live up to 3.5 years or more with appropriate care.

Guppy can easily live in captive condition. They are unpretentious and should be kept in a group of five pieces of each sex. The acceptable size of an aquarium for them is 10 gallons for a couple of fish.  Water should be replaced regularly in part or in full. The optimum temperature of the water should be 24-26 °C. When the temperature drops, they can stop breeding. The bottom of the aquarium should be covered with soil substrate.

Freshwater Angelfish

The freshwater Angelfish (Pterophyllum scalare) is the most popular aquarium fish due to their unique shape and their interesting personalities.  In the general aquarium, angelfish is easily compatible with fish of their size and temperament.

Photo: Freshwater Angelfish

The angelfish has a typical body shape resembling a crescent.  There are several types of coloring: pearl, golden, black, etc. Many have dark stripes on their bodies, and their eyes have a red tint. The size of the fish ranges from 15-25 cm in length. The females are larger than males. They have several color types. They can live up to 10 years or more with appropriate care under captive condition.

The freshwater angelfish are not selective eaters. They take live foods such as bloodworm, brine shrimp and daphnia. They also prefer to eat flakes, frozen and freeze dried food.

A large aquarium is required for proper maintenance of angelfish. In this case, aquarium tank should be at least 20 gallons. It should be kept in an abundantly planted tank with vegetation, with enough space in the center, because these fish are very active and love the space.

Water temperature for angelfish should be around 25 0C (77 0F). The aquarium should have dense vegetation with sufficient space for swimming.  For breeding, it is better to allow the fish to choose their own partners. They need to be deposited in a separate aquarium. The presence of the aquarium plants with wide leaves is very important.

They can breed in captive condition with a pH level of 6.5-7.5 and temperature of 74 – 84 °F (23 – 29 °C). Generally, they are peaceful fish but become aggressive territorial during breeding.  They prefer to lay eggs on a vertical or diagonal surface in the aquarium.

Gourami

It is another type of unpretentious common freshwater aquarium fish. They are very popular among the aquarists which belong to the Osphronemidae family of Class Actinopterygii. They have a special organ ‘the gill labyrinth’. As a result, gourami is able to breathe atmospheric air. Their body is flat and elongated. The most common colors are honey, pearl, gold, marble etc. The size of the fish is ranged from 5.0-12 cm and can live up to 5-6 years or more. During the breeding season, the body color becomes even more bright and expressive, and the stripes on the body also become darken.

Photo: Gourami Fish

Gourami is relatively well suited to most community aquariums. The tank should have fine to medium size neutral colored substrate. Optimum water temperature for gourami should be between 74-79 0F (24-26 0C) with a pH of 6.0-7.5. They prefer to live in a planted aquarium with live aquarium plants such as Cryptocoryne, Java Fern and Vallisneria.

Some Popular Gourami Species

Gourami should be kept in non-aggressive tank-mates of similar size. In this case, Dwarf Cichlids, characins and other labyrinth fish are suitable as tank-mates.

Gourami can breed in captivity but nursing of fry is difficult. During the spawning season, the male builds a nest among the floating plants. The male takes care for their baby fish but the female very rarely takes part in the process of caring for the offspring. Once the larvae hatched, the adult fish need to be removed from the breeding tank. To feed the young, you should offer infusoria and rotifers. The labyrinth organ develops gradually, so the first time you need to pay special attention to the water quality and its enrichment with oxygen. 

Swordtail

The Swordtail (Xiphophorus hellerii) is an extremely popular aquarium fish among the aquarium enthusiasts due to their hardiness and coloration. It is also known as the Green Swordtail or the Red Swordtail. In the wild, the body is olive green in color.  Sides of the body are red and yellow in color and fins bear colorful speckles.

Photo: Swordtail

The Swordtail belongs to the family Poeciliidae of order Cyprinodontiformes. In nature, it is found in Central America, Southern Mexico, and Guatemala. It prefers quiet water bodies such as lower reaches of rivers, lakes, lagoons, but it can also be found in Mountain Rivers with rapid flowing water.

It has a dense, elongated and laterally flattened body. The head is small with large eyes while the mouth is turned up. This fish has various colors breed with fins of different shapes. The most common color is red. In nature, the color of males is brownish-olive, with a greenish tint on the back but on the sides red stripes are present. It is omnivorous, feeds on any live, dry and vegetable feed.

Males have gonopodia (genital copulatory organ) and a lower ray of the caudal fin strongly grows to form a sword like apparatus. Hence, it is called the swordtail.  The long ‘sword’ is painted in green, yellow, orange, reddish color and edged with a black stripe. In nature, males grow up to 10 cm (excluding the length of the sword) while the females up to 12 cm. Females are larger in size with painted pale color and they have no sword-like apparatus. In mature females, the ‘spot of maturity’ is clearly visible, which is located in front of the anal fin.  

The swordtail is an active and peace-loving fish. It prefers to stay in the upper and middle layers of water. You can keep it in the general aquarium, which should be spacious.  Some males may behave aggressively towards other individuals of their species. It is better to keep in groups with a predominance of females. It prefers to live in densely live planted tank with enough free space for swimming. The plants should be small-leaved, reaching the surface of the water, among them, are the desirable Indian Limnophila, floating plants like Riccia where the fry can find shelter. Pebble of medium size will be suitable as a ground; lighting should be saturated, close to natural.  It prefers good water parameters with a hardness of 15-25 0 dGH; pH of 7.0 - 7.5 and a temperature of 20 - 25 °C. The tank should also have good aeration and filtration system. Weekly water changes up to 30% of the volume of the aquarium should be done.

It is a viviparous fish. Its pregnancy lasts 4 - 6 weeks. The breeding tank should have live aquarium plants. The pregnant female can give birth up to 200 fry. Newborn fry are 8-10 mm in length. Immediately after birth, the fry begin to swim and eat. Newly hatched Artemia nauplii are fed with Cyclops, boiled egg yolk, chopped spinach, algae etc. With good nutrition, the young grow quickly. At the age of 3-4 months, the sword-like apparatus grows in males.

Cherry Barb

Cherry Barb (Puntius titteya) is another very popular aquarium fish. It belongs to the Cyprinidae family of order Cypriniformes. It is distributed in Southeast Asia. It inhabits in standing and slow flowing water bodies where the dark silty bottom is available.  It has an elongated body with strongly curved back profile and lateral line is incomplete. Mouth is small with one pair of barbells. Body color can vary depending on the living conditions and health of the fish. Cherry-red color dominates in the male body, the back is darker, and the belly is lighter.

Photo: Cherry barb

From the snout, a black stripe extends across the eye and the middle of the caudal fin. Under the black stripe, rows of dark spots are sometimes visible. Gill covers are reddish in color. A fin, especially anal is reddish with a narrow dark border. The female fish has comparatively less brightly colored. Its body is yellowish-brown in color with a faint dark stripe while the fins are yellow in color. It grows up to 5 cm in length. Cherry barb eats live food such as bloodworm, daphnia, Corethra, Tubifex, vegetables such as algae, scalded lettuce, spinach, dandelion, and high-quality dry flake food.

Cherry barb is calm, gregarious and a little shy fish. Males constantly compete with each other without causing any damage to each other.  They can be kept in a group of 6 or more individuals. They prefer to stay in the bottom and middle layers of water where shady places are available.

The tank should be 20 liters for per pair of fish with dark soil and muted top lighting. The tank should be decorated with thickets of plants, various shelters such as stones, snags and free space for swimming. Cherry barb loves clean, well-settled water with a hardness of 6-18 0 dGH, pH of 6.0-7.0, and temperature of 23 - 26 0 C. Powerful filtration and aeration is required.  20-25% water should be changed every week.

For breeding purposes in captive condition, they need 20 liters of the tank with a water level of 15-20 cm. The breeding tank should also have aquarium plants like Cryptocoryne which can be planted in the center of the aquarium.  Before spawning, parents should be kept separately and fed abundantly for 7-10 days. In this case, males should be fed with live food while females with a great vegetable supplement. To stimulate spawning, a partial water change should be done.

The breeding tank should also have good water parameters with a hardness of up to 8 0 dGH, pH of 6.8, and a temperature of 26 - 28 0 С. The female lays 250 eggs in thickets of plants. Spawning lasts about an hour and the incubation period is about 24-36 hours. After another three days, the fry begin to swim and eat. The fry should be fed with rotifers and Cyclops nauplii. With good feeding, the fry grow quickly and at the age of 3 months, you can already distinguish between males and females.