Mention “African cichlid” to hobbyists today, and they will immediately think of the cichlids from the Lake Tanganyika or Malawi. From the early 1900s until about 1970, if you mentioned this same thing to a hobbyist, the fish that would pop to mind is what we today call the common krib (Pelvicachromis pulcher). Back then, it was known as Pelmatochromis kribensis, though this name was invalid. However, the “kribensis” part of the name stuck and is today often shortened to just plain “krib.”
The wild krib is found in West Africa in the Niger River delta along the coast. It is found along weed-choked banks, and among rocks and fallen branches in clear streams. Kribs are found all the way from brackish water along the coastal plain to acidic jungle streams way up river. This makes for one hardy and adaptable fish, which is probably one of the reasons it became so popular in the early 20th century long before pH, hardness and other water parameters were clearly understood.
The krib is a beautiful fish. Unlike most fish, with kribs the female is more colorful than the male, especially when courting. Adult males are larger, reaching up to 4 inches; adult females usually barely reach 3 inches. Coloration in adult males is somewhat subdued, with golden yellow and brown-black stripes. Ripe females have a deep purple belly that intensifies as she “dances” and displays for the male to let him know she is ready to spawn.
Because they come from such a wide range of habitats in the wild, water parameters seem unimportant when keeping these fish in captivity. Hobbyists have kept and spawned them for generations in both hard, alkaline water with a pH near 8, and in soft, acidic water with low carbonate hardness and a pH around 6. As long as extremes are avoided, your local tap water should do just fine. However, like most other fish, they do not tolerate poor water quality well. Regular water changes should be part of the care regimen. A sponge filter should supply them with all of the filtration they need, though more elaborate filters can be used.
They will do well in a community aquarium. A planted aquarium would be ideal, as it resembles their native habitat. You can even keep multiple pairs in an aquarium of at least 55 gallons. Provide enough caves so that each female will have at least one. They do well with other peaceful fish. A planted display with other medium-sized African fishes, such as Congo tetras, maybe a few butterflyfishes at the surface and an elephantnose would make a spectacular sight.
Feeding couldn’t be easier. They will take most flake, pellet, frozen and live fish foods. Because their mouths are down-turned, they should be fed fish foods that quickly sink. If there are other fish in the aquarium, make sure that enough fish food sinks, so the kribs can get a sufficient amount of fish food.
As kribs reach sexual maturity, it is not uncommon for a pair to form and for them to spawn in a community aquarium. The parents are hard-working and do their best to protect the fry, but normally very few survive in a community aquarium. To have better success with spawning and raising fry, it is best to set the pair up in a special aquarium by themselves.
A 10-gallon aquarium is fine for a pair, with a 15- or 20-gallon being even better. Set it up with a sponge filter or slow-flowing power filter and soft, acid water (exact water parameters are not that important) with a temperature around 80 degrees Fahrenheit. They like to do a bit of digging, so give them at least a small layer of sand or gravel on the bottom. Give them several plants and a couple of caves to choose from. I use flowerpot saucers or PVC end caps (see sidebar “Making a Cave”), but just about any closed container that has an opening big enough for them to enter it will suffice. I have even seen them using a ceramic castle in a classroom aquarium.
There is some controversy regarding the proper water conditions for spawning and raising the fry of kribs. It is said that water that is too acidic or too basic will produce a preponderance of one sex or the other. There is much anecdotal evidence to confirm this, though I have not personally observed it. Laboratory research has determined that it is not pH, but temperature, that plays a role in the sex ratios of the fry of many cichlids. This may also be what is influencing the sex ratios of kribs in the anecdotes; I have not seen any references to temperatures, so I can’t say for sure. In my own experience, at a temperature of 78 to 80 degrees and a pH of 6.8 to 7.2, I have always had nearly a 50/50 ratio of males to females. This might be something to experiment on further.
When ready to spawn, the female will intensify in color until it almost looks like she has swallowed a ripe cherry. She will arch her back and dance around in front of the male. Once she has his attention, she leads him to her chosen cave. The yellowish eggs are laid on the sides and even the roof of the cave, and the male fertilizes them. After spawning, she chases the male away, and she remains in the cave to care for the fry. Most females won’t even come out for fish food. Normally, hobbyists don’t know their fish have spawned until the female stops coming out at dinner time. It is best to leave her alone. The male will “guard” the perimeter, but is not allowed near or in the cave. Some hobbyists remove him at this point, as a really aggressive female might consider him a threat and kill him. Others leave the male with the female (I have always done this and have never lost a male to an aggressive female).
After about seven days, the female will move out of the cave with her newly free-swimming fry. The tiny fry are a deep yellow with brown camouflage patterns. The school will stay close to her as she moves about the aquarium. At this point, the male will often times play some role in caring for the fry. The parents will give the fry various signals by shaking their bodies or suddenly changing color to let the fry know when it’s safe or when they should hide. When the danger signal is given, the fry instantly dive for cover and are difficult to see.
Feeding the fry is fairly easy. They are large enough to take newly hatched brine shrimp. They will also take finely ground powdered fry foods and even pick at the flakes fed to the adults. In addition, I always add some Java moss to the aquarium. The fry will graze on the small animals (microfauna) that live on and among the tangled stems of the moss. As the fry grow, they become more adventurous and pay less attention to the signals from the adults. At this point, it is best to remove the adults and let the fry grow without them. The fry will grow quickly. At about 2 months, they should be more than 1 inch long. If you have a good spawn, you should have 75 to 150 juveniles, at which point you can start searching for new homes for them. This next generation should be ready to spawn for the first time at about 8 months or so.
If you reach this point, congratulations! You have successfully completed another Adventure in Fish Breeding.