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There are three species of Pseudocrenilabrus, all of which get offered for sale on a regular basis. They are superb aquarium fish, combining nice colours, interesting behaviour, and relatively small size. None are delicate, and all can be recommended as good fish for aquarists unfamiliar with cichlid maintenance and breeding. They are mouthbrooders, which immediately sets them apart from the other cichlids of similar size commonly kept by aquarists, such as Mikrogeophagus or Pelvicachromis. Most of the mouthbrooding cichlids are either rather large (like the South American Eartheater cichlids) or else have exacting demands in terms of water chemistry (as is the case with mbuna). These little mouthbrooders consequently make a nice alternative, and give the casual aquarist an easy way to observe one of the most fascinating and complex of all cichlid behaviours. Pseudocrenilabrus taxonomy and identification Three species are currently recognised: Pseudocrenilabrus multicolor, Pseudocrenilabrus nicholsi, and Pseudocrenilabrus philander. Some authors divide these yet further, or at least suspect that some local varieties are in fact distinct species,. Other authors have suggest that there is only a single species of Pseudocrenilabrus but that it happens to be very variable and occurs in numerous morphs depending on where it is found, which would explain why nowhere in Africa do two or more species live in the same place. Be that as it may, from the aquarists perspective the only thing that matters is that one species or variety will happily hybridise with all the other species and varieties, so it is critically important to keep them apart. Pseudocrenilabrus nicholsi is easily identified and readily segregated, but the variability of Pseudocrenilabrus multicolor and Pseudocrenilabrus philander could cause confusion among aquarists and retailers. As a general rule then, it is wise to keep batches of fish bought from one retailer isolated from any fishes in the genus obtained from another retailer or at another time unless you are sure they are of the same species and the same variety. This can be simplified somewhat with any fish sold as Egyptian mouthbrooders as these will almost certainly be the River Nile variety of Pseudocrenilabrus multicolor. But anything sold as Lake Victoria Pseudocrenilabrus multicolor or the various forms of Pseudocrenilabrus philander should be handled with a bit more care and kept apart from other fishes of the genus unless you can positively identify that both fishes are from the same species and variety. Telling the males of the three species apart is not especially difficult. Male Pseudocrenilabrus multicolor are probably the least showy of the three species, with colour limited to blue edging of the scales on the flanks and some vivid red and blue speckles on the unpaired fins. Male Pseudocrenilabrus philander are similar but with more intense colours, the blue edging on the scales so extensive that it practically covers the middle and back half of the animal contrasting vividly with the shiny yellow head. The edge of the dorsal fin is black, and the pelvic fins are coloured black as well. Male Pseudocrenilabrus nicholsi are arguably even more attractive, for while they don't have quite so much blue on the flanks as Pseudocrenilabrus philander they do have more red, and the contrast between the two colours is very eye-catching. The females of all three species are virtually identical to each other. In all cases, they are smaller than the males and far less brightly coloured, tending to be drab metallic yellowy-green fish with only a few flecks of colour on the face and fins. Male Pseudocrenilabrus multicolor and Pseudocrenilabrus nicholsi reach about 8 cm in length, the females a little less. Some varieties of the subspecies Pseudocrenilabrus philander dispersus are said to get substantially larger in the wild, in the case of the males, up to 13 cm, but these are uncommon in the hobby, and most male Pseudocrenilabrus philander only get to about 10-11 cm at most, the females slightly less. Males of all three species are territorial, but of the three I have found Pseudocrenilabrus nicholsi to be by far the most aggressive. Females tend to be inoffensive and generally keep to themselves. On their own at least, they could be kept in a community aquarium with little fuss. General aquarium care In terms of water chemistry, these fish are very adaptable being found in a variety of waters and in fact the best approach is simply to adapt them to whatever water conditions you have at home. Regular water changes to keep ambient levels of nitrate as low as possible are actually much more important than concerns about pH and hardness, though the ideal is perhaps neutral to slightly alkaline water with a moderate level of hardness. As far as temperature and filtration go, these fish aren't fussy. A temperature around 25žC (77žF) will work well, and if kept without messy tankmates then even a simple air-powered sponge filter of reasonable size could be pressed into service with good effect. Digging is limited to the production of a spawning pit by the male, and even then aquarium plants are generally not uprooted. Giving the fish an open sandy area for digging is certainly advisable if only because it allows the aquarist a chance to observe this aspect of their behaviour. As well as sand and plants, it is also important to include lots of caves in a Pseudocrenilabrus aquarium: the females will especially welcome hiding places as somewhere to avoid male attention. Mixing Pseudocrenilabrus with other tankmates is challenging but not impossible. The key thing is that the male fish are highly territorial but their aggression is limited to fishes on or close to the substrate. Fast-moving fishes that swim in the middle and upper levels of the aquarium are essentially ignored. Pseudocrenilabrus are inept predators, and while they can and will eat very small fishes such as Neons or guppies, larger species such as rainbowfish, Congo tetras, silver dollars, and giant danios make excellent tankmates. In fact, the addition of surface-dwelling tankmates as dither fish will encourage the mouthbrooders to swim in the open more readily. Combining Pseudocrenilabrus with other cichlids is not advised though. Smaller and more gentle species, such as kribs and rams, are likely to be bullied mercilessly, whereas bigger fish such as jewel cichlids and mbuna will simply repay any aggression back with interest, invariably leading to the diminutive mouthbrooder getting harmed or killed. Feeding Pseudocrenilabrus is not difficult as they will eat most foods, including flake and small pellets. Frozen or live bloodworms are a favourite, but other small invertebrates such as daphnia and brine shrimp are thoroughly enjoyed as well. Wild fish are somewhat omnivorous, and the addition of algae to their diet, through the use of Spirulina-enriched flake for example, is a good idea. Social behaviour As is probably clear by now, males aggression is the trickiest aspect of keeping Pseudocrenilabrus. In the wild, males build and defend rather large territories about the size of the average aquarium. For this reason, it is impossible to keep more than one male in a single tank. Furthermore, it is also very difficult for a female to leave a males territory, meaning that as far as he is concerned, she's in his territory for the purposes of mating. If the female happens to be carrying eggs already, she won't respond to his advances and he is apt to become short-tempered. In a small aquarium, it is all too easy for an aggressive to male to end up killing a mouthbrooding female. There are some workarounds for this, the simplest of which is simply to remove the female to a breeding tank once she's carrying eggs. This approach has several advantages. Firstly, it secures her safety and that of her brood. Secondly, it makes it easier for the aquarist to provide food for the fry once they are free swimming. Finally, once the fry are free swimming, the female can be left in the tank safely for a while and fattened up before being re-introduced to the male. This is very important because while mouthbrooding these fish cannot feed, and after a couple of weeks of this her energy reserves will be heavily depleted. She could just as easily be moved into a community tank for the this holiday period, as she isn't in the least aggressive. Either way, allow her a month or two to build up her strength before even thinking about having her raise another batch of babies. An alternative option is to set up a large tank (180 litres or more) and maintain one male with half a dozen females. Install plenty of rockwork and plants, and then add some dither fish to keep the top half of the tank nice and busy. Under such circumstances, the male should be too unable to direct all his energy towards a single female, and by being generous with space and hiding places, females will at least be able to get some peace by swimming outside the males territory when they want to. Females signal to males that they wish to mate by entering their territory, in particular by swimming into the spawning pit that the male has created. Females that stay outside this area are of no particular interest to the male, and on the whole he will ignore them. This is why giving these fish a large aquarium is so important if you want to keep a stable harem of specimens; given space, the male and females can separate themselves as required. If you're only interested in keeping a pair, then using a two-tank method will work better, with a 60-litre tank being about right for the male and a 30-litre tank adequate for a brooding female and her fry. Pseudocrenilabrus are advanced mouthbrooders in the sense that eggs are fertilised in the mouth rather that on the substrate, but in reality fertilisation may occur inside our outside the mother's mouth. The female lays the eggs on the substrate and then picks them up in her mouth, while she's gather them up, the male will often try and fertilise the eggs there and then, but usually she gathers them up too quickly for him to be completely successful. She then nips at his anal fin and vent, causing him to discharge more sperm fertilising the rest of the eggs. There is some debate about whether the orange patch on the anal fin of the male is an egg-mimic similar that seen on the fins of many Haplochromis. This is because female Pseudocrenilabrus don't consistently target the patch when mouthing the males anal fin, but instead seem to focus on the top half of the anal fin closest to the vent. Raising the fry Male fish play no part in the rearing of the eggs or fry, and everything comes down to the female. For this reason, conditioning the female before introducing her to the male is very important. They are sexually mature well before they reach full size, and females will be able to breed as small as 4 cm. Smaller females are less able to survive the rigours of mouthbrooding though, and there's a good argument to be made for separating small males and females so that the aquarist can feed them up a bit and let the female grow some more. This is especially true if the fish have been recently imported, as they are unlikely to have been feeding properly during shipping and handling. If they are already mouthbrooding, small females can be quite easily separated from their young by using a turkey baster. Turkey basters are useful bits of equipment for any aquarist, being handy for spot-removal of dirt from aquaria and directing food into filter feeding animals like corals and clams, but in this case they can be used to force the female to disgorge any fry without causing her undue stress. There's no real advantage to forcing her to spit out the eggs as she'll do a much better job of keeping them clean and fungus-free than the aquarist will, so you may as well let her brood the eggs until the fry are free swimming. To use the turkey baster, remove the rubber bulb, put the baster under water, and then place the female into the tube part of the device with her head pointing towards the nozzle. Put the bulb back onto the baster and then raise the baster above the water line. Suction will keep the water (and the fish) in place. Dip the nozzle into tank, and then gently squeeze the bulb. This causes water to flow through the gill slits and into the oral cavity, pushing her mouth open and (hopefully) the babies out. Once the babies are out, they can be scooped up with a net and transferred to another tank, and the female can be released and left to rest for a while. Freed of the task of caring for her offspring, she will quickly begin eating again, usually within a few hours, and the aquarist can either grow her on or condition her for another breeding as required. The larger the female, the bigger the broods tend to be. Some aquarists have reported broods of over a hundred from some females, but that seems exceptional, and my own experience pegs the brood sizes at a much lower level, one or two dozen being typical for small females, and perhaps thirty or so for more mature specimens. Once the fry emerge from the mother's mouth they will immediately begin foraging for food and this needs to be fairly small. Newly-hatched brine shrimp and other small live foods generally work best, but good results have also been obtained with liquid fry foods and powdered flake. Envoi Pseudocrenilabrus are delightful fish, admittedly not the easiest dwarf cichlids to put with community fish, but full of interest and brilliantly coloured. The only real problem is making sure that the female doesn't get hammered by the male when she's carrying eggs or otherwise uninterested in mating, but that's easily solved by transferring her to a ten or twenty gallon tank where she can rest and raise her brood safely. It is a shame that Pseudocrenilabrus philander and especially Pseudocrenilabrus nicholsi are relatively infrequently traded as both of these show-stopping fish as nice as anything in a reef tank, but when they do turn up they aren't expensive and they certainly aren't difficult to keep. All in all, these miniature mouthbrooders make a fun alternative to kribs, convicts, and all the other standard-issue small cichlids for beginners. Species boxes Pseudocrenilabrus multicolor Size: Males to 8 cm, females smaller Distribution: Eastern Africa from Egypt to Tanzania Water chemistry: pH 7.0, 10-15žDH Temperament: Males are territorial, but this species is perhaps the most tolerant of tankmates Notes: Highly variable, most aquarium fish are commercially-raised members of the Nile River variety Pseudocrenilabrus nicholsi Size: Males to 10 cm, females smaller Distribution: Congo Water chemistry: pH 6.0-8.0, 10-20žDH Temperament: Males are exceptionally territorial Notes: The least frequently traded species, but exceptionally colourful Pseudocrenilabrus philander Size: Typically up to 11 cm, females smaller Distribution: Southern Africa from Congo and Tanzania to South Africa Water chemistry: pH 7.0, 10-15žDH Temperament: Males are territorial Notes: The largest species, some varieties reaching up to 13 cm in length |
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