It's Dwarf Crenicichla Time!Author: Radek Bednarczuk
When most people think of South American cichlids, they think of the popular discus, angelfish, apistos, and eartheaters, but the vast waters of the Amazon are also home to other interesting and colorful cichlids, such as those in the genus Crenicichla. These are usually seen by hobbyists as aggressive, large, and unsuitable for a community tank, but some of their smaller cousins are actually ideal for community tanks.
With over 100 species and still growing, the genus Crenicichla was divided into various groups. Dwarf Crenicichla—species that do not exceed 12 to 14 cm (4¾ to 5½ inches) in length—have been placed in the wallacii group. Some of the species in this group are Crenicichla urosema Kullander 1990, C. virgatula Ploeg 1991, C. heckeli Ploeg 1989, C. wallacii Regan 1905, and the most popular ones, C. compressiceps Ploeg 1986, C. notophthalmus Regan 1913, and C. regani Ploeg 1989. There are also many interesting species that have not been scientifically described, which can be found more and more often in the aquarium trade.
The group is characterized not only by their small size, but also by the fact that the females usually possess ringed, eye-like black dots on their dorsal fins. These cichlids inhabit the waters of South America, which, depending on the species, can be still or rapidly flowing. Found in still waters are C. notophthalmus(which lives around the Rio Negro) and C. regani (which inhabits the Rio Trombetas). The latter, rheophilic (fast-water-loving) group includes, for example, C. compressiceps (which inhabits the Rio Tocantins drainage), Crenicichla heckeli, and C. urosema.
The Dwarf Crenicichla Aquarium
Although these cichlids are small in size, keep in mind that they are territorial fish that become quite aggressive during the mating season, and the males of some species have rather large territories. There is also significant intraspecific aggression among these cichlids.
The minimum tank length for a few young, sexually immature specimens is 100 cm (40 inches), and its width should be 50 to 60 cm (20 to 25 inches). The height is not as important, as these fish spend the better part of the day close to the bottom of the aquarium.
One way to limit the aggression between specimens is to only keep one or two mated pairs from one species. These fish can be kept with eartheaters, catfish, and larger cichlids, and you can keep them with other dwarf cichlids, but make sure they are too large for the Crenicichla to eat.
Theaquarium should include numerous hiding places in the form of driftwood, stones, leaves, or ceramic pipes. These hideouts can become potential spawning sites as well as places where the fish lurk for most of the day.
The substrate should consist of sand or small stones. This somewhat minimalist, austere decor of the aquarium can be enlivened with live plants—Microsorum attached to wood or stones, Echinodorus, and Cryptocoryne would all be suitable, as well as other plants well adapted to the physical and chemical parameters of the water.
The lighting of the tank should not be too bright because that could frighten the fish and make them shy. The temperature should be around 28°C (83°F), and the pH will depend on the species being kept. Usually the pH will fall in the range of 5.5 to 6 for C. notophthalmus and 6.5 to 7 for the more tolerant C. regani. The water hardness should be around 5 to 10 dGH.
Many aquarists keep dwarf Crenicichla at a pH close to 7, a general hardness of 10 to 13 dGH, and a temperature of 26° to 27°C (79° to 80°F). Under such circumstances, even slightly decreasing the pH and hardness, raising the temperature to 29° to 30°C (84° to 86°F), and adding tannins should stimulate these cichlids to breed.
A key factor to maintaining these fish in excellent health is very good biological filtration and aeration, as well as ideal sanitary conditions in the tank. Weekly water changes should be performed using water with the same physical and chemical parameters as the water already in the tank. Neglect can cause increased susceptibility to bacterial infections and shorten their lifespan. These fish can reach at least four to six years of age if conditions are good.
The Crenicichla that inhabit fast-flowing streams should have the opportunity to enjoy a brisk water current in the aquarium, which can be provided by an internal filter equipped with a diffuser directed at a stone or a piece of wood. In contrast, the species that live in still, quiet waters should not be subjected to a strong current in the aquarium, as that could cause them discomfort.
While it is commonly believed that Crenicichla need live food and live food only, this is not the whole truth. It is naturally difficult to acclimate the wild-caught specimens to dry food, but most of the species reproduce in captivity, and there is no trouble feeding captive-bred fish dry foods that sink to the bottom.
The species in this genus are usually typical predators that prey on other fish, and their elongated bodies and wide, long, massive snouts show the adaptation to this lifestyle. However, some species feed on insects, such as C. compressiceps. Good foods for all Crenicichla would be frozen krill, glassworms, bloodworms, and adult Artemia.
A good method to provide variety in their daily menu is a mixture that can be prepared at home by grinding the following ingredients: shrimp, marine fish fillets, spinach, and a small addition of green peas.
If you want to use live food, you can breed livebearers. Some hobbyists simply place a net or slotted breeder in the Crenicichla tank and put a few livebearer females inside. Eventually they will give birth to their young, which in turn serve as an excellent food source for the cichlids. It is a good method to encourage a chosen pair to spawn, as well as a food source during long absences. It can also work for fish that cannot be weaned onto dry food.
Since you need a mated pair before you can breed the fish, there are two ways to obtain one—they can be bought from a trusted breeder, or you can buy a few young fish and wait for them to pair off on their own. When buying a few young fish and allowing them to pair off naturally, it is best to separate the mated pairs into an aquarium of their own when they form.
The next step is stimulating the pair to spawn. Begin by lowering the pH and hardness, raising the temperature, and performing one large water change in the amount of 50 to 60 percent. Some people change the water every few days.
A good way to obtain excellent water for spawning purposes is to use RO-filtered water enriched with mineral salts available in the aquarium trade. It is also worthwhile to feed the pair daily with large amounts of live food.
Hiding places are an important element in the breeding tank, preferably ceramic pipes in which the eggs will be laid. If an external filter is used, its inlet should be covered with a sponge so the young are not accidentally sucked in. It is also good to add tannins to the water, which will protect the eggs from fungus.
As typical among cichlids, the spawning is preceded by spectacular courtship rituals: The male will display to the female, spread his fins, etc. Courtship can last for a few days, and the female will then occupy one of the hiding places (such as a ceramic pipe), scrupulously clean its walls, and then lay eggs (often attaching them to the ceiling), which are then fertilized by the male.
After the spawning is over the female tends the eggs, fanning them and picking out the eggs that have gone white, while the male protects the territory (the cave with the spawn inside) and chases other fish away. After three to five days, depending on the temperature, the larvae will hatch. In a week, after the yolk sac is absorbed, they can be given freshly hatched Artemia and microworms. The parents care diligently for the growing fry, and brood care can last for a few weeks, or even longer.
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