The New Guide to Aquarium
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The New Guide to Aquarium Fish A comprehensive and authoritative guide to tropical freshwater, brackish, and marine fishes Mary Bailey and Gina Sandford ULTIMATE EDITIONS Ciclilids Qchlids (family Cichlidae) origi- nate primarily in tropical America and Africa, with a few species in the Middle East and Asia. They are mainly freshwater fishes, though a few species require or tolerate brackish conditions. Size - adult Standard Length (SL) - 3 ranges from 2 cm to 91 cm ( /4 in Who's watching who? Cichlids, especially large ones, show considerable interest to 36 in) with a similar diversity in in the world outside their tank, and can become real pets. This is a female form, diet, and behaviour. Some Nandopsis do\ii, one of the largest species and a real character. species are very colourful and are thus attractive aquarium Cichlid Behaviour and Its occupants. Many aquarists are, Management however, attracted by their All cichlids practise brood care, interesting behaviour, character, guarding both eggs and young. and apparent intelligence; large This ensures a high survival rate, specimens in particular can so clutch size is small compared become genuine pets. to that in egg-scattering fishes, Cichlids can be divided into a which rely on sheer numbers of number of more or less discrete eggs for genetic survival. groups, based largely on geo- Cichlids have two brood-care graphical distribution, but also strategies: substrate brooding and habitat, size, diet, and behaviour. mouthbrooding. In the former, Before discussing the major (normally) adhesive eggs are laid Teleogramma brichardi is a cave- groups, however, we must present on a "spawning substrate", for spawning rapids cichlid from the Zaire an overview of "cichlid psy- example a stone, plant, or piece of (Congo) River. The large eggs are opaque even when fertile, and are chology" — how they behave, and, wood; then guarded against more important, why. A thorough tended by the female alone. The fry are predators, kept clean by regular correspondingly large. understanding of this is essential "mouthing", and fanned with the to their successful maintenance. pectoral fins to ensure a constant supply of oxygenated water. Both parents may share these duties, or one (usually the female) may concentrate on tending the eggs while the other guards the breeding territory. When the larvae hatch they are often placed in a pre-dug nursery pit, and sometimes moved at regular intervals to new pits. Once free- swimming, the fry may be This Cichlid is one of the smallest, Cichlids are noted for their brood care: Lamprologus ocelatus a tiny Lake escorted around in search of food, or allowed to forage, Pelvicachromis pulcher (the krib) is easy Tanganika shell-dweller. This is a male to keep, easy to sex, and easy to breed, female are even smaller independently but under and can be kept in the general supervision, in the breeding community. This is a female guarding territory. Brood care usually fry. continues until the parents are guarded like substrate-brooder ready to spawn again (which may young. Some species have be from 10 days to several months, eggspots, while others have depending on the species). evolved different egg dummies This strategy is often known such as "genital tassels" and as "substrate spawning", and is egg-like tips to the pelvic fins. further divided into "open Many tilapiines are, however, brooding" and "cave brooding", A pair of Tropheus duboisi "yellow substrate-brooders, and where according to the location of the band" spawning. The female (left) is mouth-brooding has evolved it spawning substrate. It requires a nuzzling the vent area of the male, often appears less advanced strong pair bond which may last ingesting milt to fertilize the eggs than in the haplochromines. already in her mouth. for a single spawning episode, a Mouthbrooding has also breeding season, or life. In some arisen, quite independently, in species a male may bond with some American Cichlids but is several females ("harem far less common. polygyny"), each holding her own Breeding may be seasonal or breeding territory within his continuous. The former is the "super territory". norm in bodies of water affected Mouthbrooding, by contrast, dramatically by climatic change, protects the eggs and young in and is often triggered by the A brooding female Haplochromis the mouth of one or both par- pyrrhocephalus, one of the Lake onset of the rains and a con- ents until they are old enough or Victoria "haps". Note the comitant increase in food supply large enough to stand a good characteristic distended (with fry) and available territory (flooded chance of survival alone. throat and "pursed" lips. areas). Piscivorous species may Mouthing and fanning are spawn later when their food sup- replaced by the drawing of clean, ply is augmented by fry of other oxygenated water through the fishes! Some species raise more mouth by gill action. This, coup- than one brood during a breed- led with a reduction in or cess- ing season, often with the same ation of food intake, imposes a partner. The pair bond considerable physical strain on commonly dissolves at the end the parent(s). of the breeding season, with a The majority of mouthbrooders new partner being selected next belong to one of the two main A Labeotropheus fuelleborni (orange time. morph) releasing her fry. lineages of African Cichlids, the Continuous breeding is nor- haplochromines, in which eggs before collection by the female, mally found where changes in the and fry are incubated by the but in many species males have climate have less effect, for female alone (maternal mouth- ocelli, the colour and size of example in large lakes. Over- brooding). Upon release, normally eggs ("eggspots"), on the anal population is prevented by cycli- after about three weeks, he fry fin, and in trying to collect cal fluctuation in food supply and are often abandoned. Males do these the female ingests sperm, breeding success; when the food not bond with females, but hold released from the nearby vent, supply is good females produce spawning territories, often to fertilize the real eggs that are large clutches, but the resulting centred on laboriously con- already in her mouth. population explosion depletes the structed "nests", from which they In tilapiines, the other African food supply and reduces breeding display to potential temporary lineage, brooding may be mater- success until the food supply partners. Frequently males hold nal, paternal or biparental, the recovers. In cap-nvhy constant adjacent territories and compete last usually involving a pair bond abundant food may lead to for females ("arena breeding"). and shared territory, as in sub- unnaturally frequent and/or large The non-adhesive eggs are laid in strate brooding. Brood care may clutches and excessive physical the nest. Sometimes they are continue after release, with fry drain on the female, with gill fertilized returning to the mouth or being strain a serious danger in mouthbrooders. Courtship may be stormy. A pair of Nandopsis octofasciatus Qack Dempseys) mouthfighting. Most cichlids can be induced to Plants can be protected by breed in captivity (some need planting in pots, or between rocks little persuasion), but it must be and/or pebbles; or omitted. understood that in some species Equipment can be fixed in place, there is a downside to their and heavy, immovable, decor breeding behaviour. This has used. The environment should be given the entire family an often tailored to natural behaviour - you undeserved reputation for being will never achieve the reverse! Substrate spawners such as difficult, destructive, aggressive, A fish which needs to hold a Amphilophus citrinellus often dig and so on. The worst problems private territory to attract a mate nursery pits. can be avoided by understanding (mouthbrooders) or raise a family the reasons for their actions and (substrate brooders) will quite taking their behavioural (as well as justifiably regard tankmates as physical) needs into account. competitors, intruders, or potential Digging is a natural and fry-predators, and do its best to instinctive part of cichlid behav- eliminate such threats. Even if the iour, and attempts to curb it, for aquarist is aware of the need for example by having no substrate, an exclusive territory, he rarely are cruel. "Aquascaping", some- comprehends the amount of space times with uprooting of plants, is required by substrate brooders. Mouthbrooders dig too, some building huge crater nests. often a necessary preliminary to Although some small species are breeding - the construction of content, in nature as well as a 120 x 40 cm (48 x 15 in) nursery pits or nests. Large cich- captivity, with an area 30-40 cm aquarium, they draw the line at lids may try to remove intrusive (12-15 in) in diameter, many sharing it. So, although many decor and equipment by brute others occupy an area the size of a species can be included in general force - and worse still, succeed! In good-sized room in the wild, and or cichlid communities, it must be general, the larger the species, the while they are obliging enough to accepted that some need their own greater the extent, and likelihood, make do with aquarium. 10 of disruption. Sometimes the hostility of the territorial male extends to the female. In nature a female can simply swim away from a male when she does not wish to breed. To stay is to indicate interest. In the aquarium she cannot swim away, the male assumes she wants to breed, and when she rejects his courtship he attacks her like any intruder -but she has nowhere to go, and may be killed. So, unless the tank is rather longer than natural territorial diameter, care Occasionally even Apistogrammas have to be "contained" with a divider.