The Cockatoo Dwarf Cichlid (Apistogramma cacatuoides)
Author: Mike Hellweg
An experienced aquarist profiles the smaller-sized, but by no means smaller-personality, cichlids that get their name from their beautiful cockatoo-crest-like dorsal fins.
One of the most spectacular species is called the cockatoo dwarf cichlid (A. cacatuoides) or sometimes just plain “cacatuoides.” They have become so popular that they are produced in quantity on Southeast Asian fish farms and are regularly available in the trade, even in big-box stores. In the past couple of weeks, I even noted some juvenile triple red cacatuoides at a local big-box store on sale for just $4 each!
The common and scientific names both come from the spectacular dorsal fin of the male. “Cacatuoides” means “like a cockatoo,” and it is an apt descriptor. The first several rays of the male’s dorsal fin are greatly elongated and are often carried erect, resembling the display crest of a cockatoo.
The wild fish don’t have the spectacular colors of domestic line-bred fish, but even their fins are spectacular. Line-bred fish with a solid red or orange dorsal have to be seen to be believed. A displaying male will catch the eye of even the most jaded hobbyist.
A Bit of History
A. cacatuoides was formally described by the Dutch ichthyologist J. J. Hoedeman in 1951 and has kept that name ever since. At times, it has been mixed up by hobbyists and dealers with A. borellii, another apisto that is spectacular and easy to care for, but that has been, for the most part, cleared up.
As males reach sexual maturity, they develop an enlarged head that seems like it continues to grow throughout their lives in all disproportion to their body size. Their mouths are huge and are used for yawning threat displays to other males. I’ve even heard experienced hobbyists declare that there’s “something wrong with that male’s head.” There was nothing wrong—it was just a fully developed, sexually mature male.
A. cacatuoides is found in Peru, Colombia, and Brazil in the drainages of the Rio Ucayali and Rio Solimoes. This part of the Amazon drainage has fluctuating water parameters that, at certain times of the year, are harder and more alkaline with a higher pH than those we usually associate with South America in general and the Amazon River basin in particular. At various times of the year, the pH can rise up to 8.0, hardness can vary from unmeasurable to what we would call very hard, and alkalinity fluctuates from zero to well over 300 ppm!
Cockatoo dwarfs are found in both white water and clear water, but not in blackwater habitats. This makes them especially adaptable to tap water here in the US, and they do spectacularly well in most hobbyists’ tanks without us having to do anything to make the water suitable for keeping or breeding.
Cover the bottom with a thin layer of fine gravel or even sand. Add a couple of pieces of driftwood with epiphytic plants like Anubias or Java fern attached, a couple of caves (new ceramic or plastic flower pots or even coconut shells with a hole cut in them), and a clump of Java moss.
As I mentioned earlier, there is no need for a heater as long as the room temperature doesn’t go below 60°F (15°C) for any length of time. If you absolutely have to have a heater, set it for 72° to 74°F (22° to 23°C).
As said before, your local water is probably fine for the very-adaptable cockatoo apisto. Instead of focusing on hitting an exact pH or hardness number, realize that in the wild, these numbers fluctuate throughout the year and hitting an exact number isn’t that important for cacatuoides. What is important is to do large, regular water changes to keep dissolved organic compounds and nitrogenous wastes in check.
I like to do a 50-percent water change every week to 10 days, though with my travel schedule, that sometimes stretches out to once every 30 days. But with just eight cacatuoides and some small livebearers as dithers in the tank, the bioload is very light and doesn’t build up very quickly in a 40-gallon (151-liter) breeder.
In order to bring them into breeding condition, I feed them live worms several times a week. I currently use live blackworms and chopped earthworms, but Grindal worms and white worms will work, too. They will also take daphnia, live adult brine shrimp, and small cherry shrimp. Surprisingly, even adults will take newly hatched brine shrimp.
They are also miniature eartheaters, especially the males. They spend much of their time digging into the sand, sometimes up to their eyes, looking for food. They’ll pop up with a mouthful of sand, move it around their mouth, and carefully squirt it out through their gills, extracting any food items as they find them.
Whenever fry are present in the tank, I always squirt newly hatched brine shrimp and microworms into the tank near the fry at least twice a day. The fry will also graze on the surfaces of the plants, nibbling at the nutritious biofilm (aufwuchs) that grows there.
The males will fight amongst themselves until one establishes his dominance. He will be the breeder. The other males likely won’t get a chance to breed and will likely be beaten up each time they venture into the open in sight of the dominant male. It is easy to tell which male is dominant—he will be out in the open, in full color, courting the females. Usually he won’t have any torn fins.
The sub-dominant males will take on a pale coloration, keep their dorsal fins clamped, and stay on the lookout for an escape route. For the sake of the fish, the sub-dominant males should be removed unless the tank is heavily planted and rather large (over 75 gallons [284 liters]).
After a short courting period, during which the male dances and displays for the female, the female leads the male to her chosen cave. Courting and guarding females take on a beautiful lemon-yellow and black coloration. The female lays her eggs on the side wall or ceiling of the cave, and the male fertilizes the eggs.
As the male can sometimes be twice the size of the female, often he can’t enter the cave and has to fertilize the eggs from outside the opening. Fertility is usually high, and the female will pick off any unfertilized eggs. Some authors report batches of up to 200 eggs, but most spawns that I’ve had averaged closer to 100 to 125.
The female guards the fry night and day until they are free-swimming and for several weeks thereafter, herding the fry around the tank and taking them from one feeding place to another. Java moss is a favorite feeding site, as it is usually home to a vast number of microscopic critters. They also find the surface of sponge filters or mattenfilters to be great grazing areas. The young grow quickly and can begin coloring up at just eight to ten weeks old.
Although I’ve found wild populations with some blue on the body and fins, I still haven’t found any quite like those unbelievably beautiful males in Van den Nieuwenhuizen’s picture. I continue to look.
I put them into a 15-gallon (57-liter) quarantine tank with a large sponge filter, a shallow layer of fine quartz gravel on the bottom, a big clump of mixed Java fern and Java moss, and a half dozen ceramic caves and coconut shells scattered on the bottom. One male, just slightly more colorful than the others, quickly asserted his dominance. By the end of the second day when I got home, there were three corpses bobbing in the current.
The four females were each in a cave of their own, and the single remaining male was out in the middle, looking like he was still wanting a fight.
I carefully siphoned about 20 fry out of the tank and left the rest with mom. She did a great job herding and raising those fry. After that, at least one of the females seemed to always be herding a group of fry. The fry were easy to raise, as they took newly hatched brine shrimp, microworms, and powdered fry food from the start. Oddly, the ones left with the mother grew more quickly than those I moved to a separate tank to raise on their own.
I’ve since noticed that with many cichlids, so much so that now I try to leave most of the fry with mom and just remove enough to ensure I get another generation in case something goes wrong. I raised several hundred fry to maturity from that group and had first generation (F1) and later F2 juveniles or pairs to sell and share for a couple years afterwards. That was one of the first apistos I successfully kept and bred, and to this day, it is still one of my favorites, though I’m still looking for some to rival those I saw in my first fish book.
A Great Starter Cichlid
I do feel I have to warn you, though. The members of the genus Apistogramma are fantastic fish and it is easy to fall under their miniature “cichlidy” spell. I speak from experience! Since I got that first group of A. cacatuoides, I haven’t been without Apistogramma in my tanks. I’ve usually got at least three or four species swimming in my fishroom tanks at any one time. You’ve been warned. Now, go get some and enjoy!
Apistogramma cacatuoides HOEDEMAN, 1951
Cockatoo Cichlid Classification:
The type locality was originally given incorrectly as Paramaribo, Suriname but this was later amended by Kullander to the “Amazon River basin, between 69°W and 71°W”. The species is currently considered widespread throughout much of the upper Amazon basin from the ríos Ucayali and Amazonas in Peru to the Solimões in western Brazil. Some populations exhibit notable differences in colour patterning.
Tends to inhabit slower-moving tributaries, backwaters and creeks in areas where fallen leaf litter collects and these may contain black, white or clear water depending on locality or in some cases, time of year.
Maximum Standard Length:
Provided adequate cover and structure is available this species is unfussy with regards to décor with ceramic flowerpots, lengths of plastic piping and other artificial materials all useful additions. A more natural-looking arrangement might consist of a soft, sandy substrate with wood roots and branches placed such a way that plenty of shady spots and caves are formed.
The addition of dried leaf litter (beech, oak or Ketapang almond leaves are all suitable) would further emphasise the natural feel and with it bring the growth of beneficial microbe colonies as decompositionoccurs. These can provide a valuable secondary food source for fry, whilst most populations will appreciate the tannins and other chemicals released by the decaying leaves. Leaves can be left in the tank to break down fully or removed and replaced every few weeks. If maintaining a blackwater population a net bag filled withaquarium-safe peat can also be added to the filter or suspended over the edge of the tank.
Fairly dim lighting is recommended and plant species from genera such as Microsorum, Taxiphyllum,Cryptocoryne and Anubias are best since they will grow under such conditions. A few patches of floating vegetation to diffuse the light even further may also prove effective. Filtration, or at least water flow, should not be very strong and very large water changes are best avoided with 10-15% weekly adequate provided thetank is lightly-stocked.
Temperature: 22 – 29 °C
pH: Commercially-produced fish are relatively unfussy but some wild populations may require values of 5.0 – 6.0 in order to breed.
Hardness: 0 – 268 ppm, again depending on origin to an extent.
Primarily carnivorous and apparently feeds mostly on benthic invertebrates in nature. In the aquarium live and frozen foods such as Artemia, Daphnia and chironomid larvae (bloodworm) should be offered regularly although most specimens will also learn to accept dried alternatives with pelleted products generally preferred to flake.
Behaviour and Compatibility:
Captive-raised fish are the recommended choice for the general community aquarium. Wild examples are best maintained alone or with small ‘dither’ fishes such as Nannostomus spp., and ideally should not be mixed with other Apistogramma.
Males are larger, more colourful and develop more extended fins than females.
Substrate spawner which normally lays its eggs in crevices or cavities among the décor. The female is responsible for post-spawning care of eggs and fry and in smaller aquaria the male may need to be removed as she may become hyper-aggressive.
Numerous ornamental forms of this species have been selectively line-bred for the aquarium trade, vernacular names for which include “sunset”, “sunburst”, “double red”, “triple red”, “gold”, “white gold”, “orange flash” and “albino“. It has also been assigned the ‘A’ number A200 under the DATZ system with possibly conspecific, related forms similarly numbered A201, A202 and A203 depending on locality.
The genus Apistogramma is among the most speciose of South American ccihlid genera with around 70species valid at present but many more awaiting description. In addition many species exist in two or more geographical colour forms which may or may not turn out to be distinct in the future. Hobbyists tend to label these with collection data if available in order to avoid mixing them and the potential of hybridisation.
Member species have also been organised into a series of species lineages, complexes and groups by authors in order to better separate them. Such lists have been augmented by fish that have appeared in the aquariumtrade and are in a state of near-constant flux. The A. cacatuoides group, for example, is contained within theA. trifasciata sublineage of the larger A. trifasciata lineage alongside A. arua plus the A. brevis, A. nijsseni, A. atahualpa and A. trifasciata groups.