I've got a blue ram cichlid...

Mikrogeophagus ramirezi is a species of freshwater fish endemic to the Orinoco River basin, in the savannahs of Venezuela and Colombiain South America.^[2] The species has been examined in studies on fish behaviour^[4] and is a popular aquarium fish, traded under a variety ofcommon names including Ram, Blue ram, German blue ram, Asian ram, Butterfly cichlid, Ramirez's dwarf cichlid, Dwarf butterfly cichlid and Ramirezi.^{[2][5][6][7][8]} The species is a member of the family Cichlidae and is included in subfamily Geophaginae.^[2][9]

Appearance and sexual dimorphism

The male M. ramirezi

Distribution and habitat

Wild ram cichlids are often more colorful than the tank bred counterparts, which suffer from poor breeding and also being injected with hormones for more color, although this makes as many as one in four males infertile. Male specimens of the ram usually have the first few rays of the dorsal fin extended, but breeding has made some females also show this. There is also the fact that, when close to spawning, female rams have a pink or red blush on the abdomen. Females also have a blue sheen over the spot just below the dorsal fin, and males do not show this. Males reach a maximum length of seven centimeters, and females are usually slightly smaller. (Please note that the black spot method of sexing does not apply for the golden and electric blue varieties of the species.)

The natural habitat of M. ramirezi occurs in the warm, (25.5-29.5 °C, 78-85 °F), acidic (pH 5) water courses in the llanos savannahs ofVenezuela and Colombia.^[5][7][10] The water at sites where M. ramirezi has been found is generally slow-flowing, contains few dissolved minerals, and ranges in color from clear to darkly stained with tannins.^[5] The species is typically found where cover in the form of aquatic or submersed vegetation is available.^[5]

Reproduction

The territorial aggression shown between males of M. ramirezi

Once sexually mature, the species forms monogamous pairs prior to spawning and the males do not tolerate other males.^[7] The species is known to lay its small 0.9 - 1.5 mm, adhesive eggs on flattened stones^[7][10][11] or directly into small depressions dug in the gravel.^[5] Like many cichlids,M. ramirezi practices biparental brood care with both the male and the female playing roles in egg-tending and territorial defense.^[5][7] Typical clutch size for the species is 150-300 eggs,^[5][6] though larger clutches up to 500 have been reported.^[10] Parental M. ramirezi have been observed to fan water over their eggs which hatch in 40 hours at 29 °C (84.2 °F). The larvae are not free-swimming for 5 days after which they are escorted by the male or the female in a dense school for foraging.^[

The ram cichlid is a popular cichlid for the tropical freshwater, community aquarium although it is not necessarily the easiest cichlid to maintain in many situations.^[5] This is because the species is often kept with other fish that are more assertive, aggressive or overly active.^[5][7] The species is innately shy and is best kept with passive dither fish, such as neon or cardinal tetras.^[7] The species will readily exhibit breeding behaviours in water of pH 5.0-6.5, though softer water encourages more regular spawning.^[5][7][10] It is easier to maintain the species in larger aquaria as the species is intolerant of common aquarium pollutants such as nitrate.^[7] The aquarium should be decorated to mimic the natural environment and is best decorated with several densely planted regions of aquatic plants, separated by open water.^[6] The species is prone to filial cannibalism of its brood if distressed.^[7] As the water must be free of pollutants, aquarium filtration is important, though water movement should not be extreme. Removing and replacing small amounts of water assists with minimizing the quantities of these pollutants and should be conducted regularly.^[10]

Numerous strains of M. ramirezi have been developed in Asia for the fishkeeping hobby. These include numerous xanthistic forms, known as gold rams, along with larger, high-bodied and long-finned varieties.^[5][7][14] Many of these varieties suffer from lower fertility, health problems or reduced brood care in comparison to wild-type specimens.^[5][6]

I've got cardinal tetras...

The cardinal tetra, Paracheirodon axelrodi, is a freshwater fish of the characin family (family Characidae) of order Characiformes. It is native to the upper Orinoco and Negro Rivers in South America.

Growing to about 3 cm (1.25 in) total length, the cardinal tetra has the striking iridescent blue line characteristic of the Paracheirodonspecies laterally bisecting the fish, with the body below this line being vivid red in color, hence the name "cardinal tetra". The cardinal tetra's appearance is similar to that of the closely related neon tetra, with which it is often confused; the neon's red coloration extends only about halfway to the nose, and the neon's blue stripe is a less vibrant blue, however.

The cardinal tetra is a very popular aquarium fish but is less widespread than the neon tetra because until recently it was difficult to breed in captivity. However, many breeders are now producing the fish; in most cases one can determine if the cardinal tetra is bred or wild caught due to damaged fins on wild caught specimens. Normally aquarists prefer to buy tank bred fish but some Brazilian ichthyologists believe that fishkeepers should continue to support the sustainable Cardinal fishery of the Amazon basin, since thousands of people are employed in the region to capture fish for the aquarium trade. It has been suggested that if those fishermen lost their livelihood catching Cardinals and other tropical fish, they might turn their attention to engaging in deforestation.

The fish might also be effectively an annual species and may have a lifespan of just a single year in nature. It lives for several years in captivity.

An entire industry is in place in Barcelos on the banks of Brazil's Rio Negro in which the local population catches fish for the aquarium trade. The cardinal fishery here is highly valued by the local people who act as stewards for the environment. It may be said that the local people do not become involved in potentially environmentally damaging activities, such as deforestation, because they can make a sustainable living from the fishery.

Perhaps due to their wild-caught origins, cardinal tetras tend to be somewhat delicate in captivity. In the wild, these fish inhabit extremely soft, acidic waters, but seem to be tolerant of harder, more alkaline water conditions; a greater concern is probably polluted tank water (including high nitrate levels.) They prefer warmer water temperatures (in the upper 70s F or warmer (20°C)), and will readily accept most forms of dry food. Captive-bred cardinals tend to adapt to hard water better than wild-caught cardinals.

P. axelrodi is also often called the red neon tetra. Cheirodon axelrodi (the original name) and Hyphessobrycon cardinalis are obsolete synonyms. The fish's common name, cardinal tetra, refers to the brilliant red coloration, reminiscent of a cardinal's robes.

Given the origins of the cardinal tetra, namely blackwater rivers whose chemistry is characterised by an acidic pH, low mineral contentand the presence of humic acids, the species is adaptable to a wide range of conditions in captivity, though deviation from the soft, acidic water chemistry of their native range will impact severely upon breeding and fecundity. The preferred temperature range of the fish is 21°C to 28°C (70°F to 82°F). The water chemistry of the aquarium water should match that of the wild habitat - filtration of the aquarium water over peat is one means of achieving this.

As the species is a shoaling species in the wild, groups of six or more individuals should be maintained in an aquarium. They will shoal with their close cousins neon tetras however, so a combination of these two species totalling at least six should suffice. Tank currents can help encourage shoaling behavior. The larger the numbers present in an aquarium (subject to the usual constraints imposed by space and filtration efficiency), the better, and large shoals in any case form an impressive and visually stunning display.

The species will feed upon a wide range of aquarium foods, though again, conditioning fishes of this species for breeding will usually require the use of live foods such as Daphnia.

Aquarium furnishings should be planned with some care. Live aquatic plants, as well as providing an additional biological filtration component that assists with nitrate management in the aquarium, provide an environment that resembles at least part of the wild habitat, and fine-leaved plants such as Cabomba are usually the plants of choice, though other plants such as Amazon Swordplants and Vallisneria are equally suitable for an aquarium housing the cardinal tetra. Floating plants providing shade will also be welcomed by the species: this is connected with the breeding of the fish, which will now be covered. A perfect biotope to promote breeding, would be lots of bogwood, a few live native plants, with dark substrate and subdued lighting with floating plants.

The species exists in a number of different colour forms or phenotypes. A "gold" and "silver-blonde" form exist in the Rio Negro drainage which have less blue in the longitudinal stripe. The normal form from the Rio Negro drainage has a blue stripe which extends to the adipose fin, while the Orinoco drainage phenotype has a stripe which stops posteriorly of the adipose. The Orinoco phenotype may represent a subspecies of P. axelrodi.

Breeding

The cardinal tetra, in the wild, swims upstream in large numbers to parts of its native river habitat that are completely enclosed above by rainforest canopy. Such waters are subject to heavy shading by the rainforest trees, and virtually no sunlight reaches them. Here, the fishes spawn in large aggregations. In the aquarium, a single pair can be conditioned for breeding, but the breeding aquarium not only needs to contain water with the correct chemical parameters cited above: the breeding aquarium needs to be heavily shaded to mimic the low light conditions of the fish's native spawning grounds. If the fishes are ready to spawn, the male, which will be the slimmer of the two fishes in outline, will pursue the female into fine-leaved plants: her fuller outline, which usually indicates the presence of ripe eggs within her reproductive tract, should be readily apparent at this point. If the female is ready, she will allow the male to swim alongside her, and together, the pair will release eggs and sperm.

Apart from the stringent requirements with respect to water chemistry, one of the major difficulties mitigating against success in captive breeding of the species is the nature of the newly laid and fertilised eggs. The eggs of the cardinal tetra are photosensitive, and will die if exposed to bright light. Consequently, after spawning, the fishes should be removed and the aquarium covered to darken it, thus providing the developing eggs with the conditions necessary for development.

Development

If the eggs are fertile, and kept in darkened surroundings, they will hatch in approximately 3 days at 28°C. Free swimming fry remain photosensitive for at least the first 7 days of life, and need to be introduced to increasing light levels on a gradual basis. During this time, they are approximately 4 mm in length, and require infusoria or liquid fry food. Newly hatched brine shrimp and other similar live foods such as sifted Daphnia can be fed to the growing fry at between 7 and 14 days of age. Growth continues at a modest rate, and the fishes assume full adult colouration only after a period of approximately 8 to 12 weeks, depending upon quality of food and aquarium water.

The characteristic iridescence of this and related fishes such as the neon tetra is a structural colour, caused by refraction of light within guanine crystals that develop within special cells called iridocytes in the subcutaneous layer. The exact shade of blue that is seen will depend upon the viewing angle of the aquarist relative to the fish - if the aquarist changes viewpoint so as to look at the fish from the substrate upwards, the colour will change hue, becoming more deeply sapphire blue and even indigo. Change the viewpoint to one above the fishes, however, and the colour becomes more greenish.

I've got bleeding heart tetras...

General

This fish is somewhat susceptible to velvet disease and Ich. This fish is sensitive to water conditions. Does not usually live more than five years. Requires frequent partial water changes.

Compatibility/Tankmates

Bleeding Hearts are generally a peaceful fish but fin nipping may become a problem, Males can be territorial. Keep them in a small school (6 or more) and try not to keep them with fish with larger fins such as angelfish and bettas. They do well in a variety of community tanks, and like most tetras they do best in groups and with bushy plants. Make a great tank mate for corydoras and other bottom dwelling species. They are peaceful when they are surrounded by their own kind with a few exceptions, just like tiger barbs. They are also mischievous, nipping at others' tails and entering their territory looking for food.

Sexing

Female is more full bodied and the male has a larger dorsal fin.

Breeding/Spawning

Hard but not impossible, They have been bred in captivity and are egg layers.

Coloration/Fins

They have a splendid body shape and, after a month or two in captivity, their colors get very beautiful, especially when fed (two or three days a week) with frozen brine shrimp. The dorsal fin of the males can become long and flowing. Both sexes have the eye-catching, blood-red spot at the heart area. Both also have the black/white patch on the dorsal fin

I've got serpae tetras...

Serpae tetras are one species of the genus Hyphessobrycon, now known as Hyphessobrycon eques. These South American tropicalcharacids are popular aquarium fishes, often identified as "Red Minor tetras". They are found in nature in the Madeira and Guaporé regions of the Amazon river, and in upper Paraguay.

In the Aquarium

A long-finned variety of H. eques

Serpae tetras prefer water temperatures ranging from 72-79°F (22-26°C). They will generally do better and show off their best colors in soft, neutral to slightly acidic water. As with any other schooling fish, they thrive in large groups and should be kept in schools of at least 6-10 fish. The tank should be well-planted, which provides shelter and hiding spots.

They have a reputation of being fin-nippers although this is disputed. If any aggression is seen in the fish, it is usually amongst themselves rather than aimed at tankmates outside of their species, especially if they are kept in large groups where they can establish a pecking order (a behavior similar to Puntius tetrazona). Their typical temperament and striking appearance (red with a black diamond on the flank) makes them an excellent addition to the community aquarium.

Breeding

Breeding, as with most other tetras, can be difficult due to there being few obvious differences between the genders. However, males are usually more slim and smaller than females. There is also a visible difference between the shape of the swim bladder, which can be seen above and behind the silverish abdominal cavity. To breed these fish, they should be given a small, dedicated breeding tank planted with thick bunches of fine-leaved plants such as Myriophyllum on which they can lay eggs. Filtering through peat moss can also be helpful. The eggs hatch in about a day.

I've got tiger barbs....

The tiger barb or sumatra barb, is a species of tropical freshwater fish belonging to the Puntius genus of the minnow family. The natural geographic range reportedly extends throughout the Malay peninsula, Sumatra and Borneo, with unsubstantiated sightings reported inCambodia. Tiger barbs are also found in many other parts of Asia, and with little reliable collection data over long periods of time, definite conclusions about their natural geographic range versus established introductions are difficult. Tiger barbs may sometimes be confused with Puntius anchisporus, which are similar in appearance.

Physical description

The tiger barb can grow to about 7 centimeters long (2.75 in) and 3 centimeters wide,(1.18 in) although they are often smaller when kept in captivity. Native fish are silver to brownish yellow with four vertical black stripes and red fins and snout. The green tiger barb is the same size and has the same nature as the normal barb but has a green body. The green 'tiger barb is often called the moss green tiger barb. People vary considerably in how green it looks to them. To some people it looks nearly black. Albino barbs are a light yellow with four stripes just barely visible.

Habitat

It has been reported that the tiger barb was found in clear or turbid shallow waters of moderately flowing streams. It lives in a tropical climate and prefers water with a 6.0–8.0 pH, a water hardness of 5–19 dGH, and a temperature range of 77 - 82 °F or 25 - 27.8°C. Its discovery in swamp lakes that are subject to great changes in water level suggests a wide tolerance to water quality fluctuations. Its average lifespan is 6 years.

Importance to humans

Green tiger barb

The tiger barb is one of over 70 species of barb with commercial importance in the aquarium trade. Of the total ornamental fish species imported into the United States in 1992, only 20 species account for more than 60% of the total number of specimens reported, with tiger barbs falling at tenth on the list with 2.6 million individuals imported. (Chapman et al. 1994). Barbs that have been selectively bred to emphasize bright color combinations have grown in popularity and production over the last 20 years. Example of colour morphs (these are not hybrids) of tiger barb include highly melanistic green tiger barbs that reflect green over their black because of the Tyndall effect, gold tiger barb, and albino tiger barb.

In the aquarium

A school of green tiger barbs in a 20 gallon tank.

The tiger barb is an active schooling fish that is usually kept in groups of five or more. They are often aggressive in numbers less than 5 and are known fin nippers. If you only keep two in a tank, one will eventually chase the other fish. Semi-aggressive fish form a pecking order in the pack which they may extend to other fish, giving them a reputation for nipping at the fins of other fish, especially if they are wounded or injured. They are thus not recommended for tanks with slower, more peaceful fishes such as bettas, gouramis, angelfish and others with long flowing fins. They do however work well with many fast moving fish such as danios, platys and most catfish. When in large enough groups, however, they tend to spend most of their time chasing each other and leave other species of fish alone. They dwell primarily at the water's mid-level. One of the best tankmates for the tiger barb is a clown loach, which will school with the tiger barbs and act as they do, and the tigers act as the loaches do. Tiger barb do best in soft, slightly acidic water. The tank should be well-lit with ample vegetation, about two-thirds of the tank space. These barbs are omnivorous and will consume processed foods such as flakes and crisps as well as live foods.

Breeding

P. tetrazona that is close to sexual maturity

The tiger barb usually attains sexual maturity at a body length of 2 to 3 centimeters (0.8 to 1.2 inches) in total length, or at approximately six to seven weeks of age. The females are larger with a rounder belly and a mainly black dorsal fin while the males have a bright, red nose with a distinct red line above the black on their dorsal fin. The egg-layers tend to spawn several hundred eggs in the early morning in clumps of plants. On average, 300 eggs can be expected from each spawn in a mature broodstock population, although the number of eggs released will increase with the maturity and size of the fish. Spawned eggs are adhesive, negatively buoyant in freshwater and average 1.18 ± 0.05 mm in diameter.

Tiger barbs have been documented to spawn as many as 500 eggs per female (Scheurmann 1990; Axelrod 1992). With proper conditioning, females can spawn at approximately two week intervals (Munro et al. 1990)

Once spawning is finished, they will usually eat any of the eggs that they find. It is usually necessary to separate the fish from the eggs after spawning in order to prevent the eggs from being eaten.