Mellow Cichlids: A Primer
Medium to large Cichlids have, in general, a reputation of aggression towards tankmates, intolerance to others of their kind, and just a bad attitude in the aquarium.
To dispel those myths, in this post we'll study what I call the mellow fellows; that is, the medium to large Cichlids that, to a lesser or greater extent, are completely passive in the aquarium. Some, of course, are more passive than others, and one or two can suddenly turn from Dr. Jeckle to Mr. Hyde in an eye blink, or will stay mellow throughout their life. For this post, I'll define medium as fish that grow to over four inches in total length, though most in the list get a good deal larger than that, and are gentle to tankmates too large to eat.
Some species in this list are ridiculously easy to find in shops, some with take some searching, but all are well worth dedicating tank space to. Keep in mind, though, that they are Cichlids, and thus can be unpredictable, but of course, the ones in this list are easily defined as passive in the aquarium.
Now, some species.
By far the most common and popular mellow fellow available is the Oscar (Astronotus ocellatus), of soft, acidic tributaries of the Amazon basin in Venezuela, Guyana and Paraguay.
Oscars, which reach 14 inches given the time and space to do so, are affable to fish too large to eat and to each other when kept in a group, if introduced all together when young. And they have, for lack of a better word, personality. They very quickly learn who feeds them, and they will do all kinds of antics to get the attention of their keeper.
A favorite is a tail slap on the surface of the water. Some jump clear of the water, landing with a huge splash. Another is the whole group at the front of the tank staring at you until you feed them. Redesigning the tank decor when things don't go their way is common. A stomach with fins, Oscars are always prepared to eat, and if you're not careful, they'll train you when, what and how much to feed them with their behavior.
In nature they live in both black and white water habitats that are quite soft and acid, even down to pH 5.5 with near zero hardness. Commercially bred for decades, they'll even live and possibly breed up to perhaps pH 7.5 with moderately hard water. However, they live and breed best in the soft and acid tank, as eggs usually don't hatch in hard water. They prefer temperatures between 75 and 80 degrees. Filtration through peat moss darkens and softens the water, which usually triggers breeding in this species.
Captive breeding has resulted in many different color morphs. Primarily it's red and orange markings on a black or dark grey-green ground, usually with an occelated orange or red circle (the 'ocellatus') at the top of the caudal peduncle. Some can be almost totally orange, some albino with light orange markings on an ash-white ground. There are dozens if not hundreds of color variations of this species. And each Oscar is as individual as a fingerprint; no two are exactly alike in markings.
If you wish to breed or just keep a group of Oscars, a 200-gallon tank would be sufficient for a group of six or eight adults. It should be furnished with just driftwood and stones, as live plants would be pointless, as they always tear them out. In larger quarters, tankmates can be schools of larger Characins, like Silver Dollars, or Cypranids like Tinfoil Barbs; in other words, schooling fish that grow too large to eat. Catfish can be the Doradids, who are so well armored even an ever- curious Oscar knows better than to touch them. Some of the larger riverine Synodontis would be OK, just make sure they grow to at least six inches. One or more of the sucker-mouthed cats (plecos) can take care of algae duties. Make sure the species grows to five inches or more.
Stay away from pictus cats and the like, because the long whiskers irritate sleeping Oscars, and as Oscars have long memories, they'll eventually kill the pictus because of that irritation. A dark substrate and background intensifies the colors of Oscars.
The larger the tank the larger and more entertaining Oscars get. In feeding, if you give it to them, they'll probably eat it. A very omnivorous fish, high-quality pelleted foods can be staple, and they like things like fresh spinach leaves, small shrimp (either live or frozen), clean live red worms, California black worms, pieces of apple and pear . . . in other words, they will eat what you give them, so make sure the quality is a high as you can make it for their continued health and vitality. Though they can be picky towards foods, their stomach will win out every time if you're persistent with foods that are good for them.
As an aside, don't feed Oscars live fish, as they are too rich for the Oscars' systems, eventually causing kidney shutdown and death. Properly kept, Oscars easily live well over 20 years.
In breeding, juveniles pair off early, and stay mated for life. Best bet is to buy eight youngsters, and select the most compatible pairs for transfer to the main tank. Oscars are flat rock spawners, and full-grown adults can lay more than 2,000 eggs. Excellent parents, the vast majority, easily 90 percent, of the fry will survive and thrive under the adults' care.
If you aren't concerned with breeding, a good-sized group of Oscars in a large aquarium is an endlessly entertaining sight.
On to Part 2
One of the long-time favorites of the aquarium hobby are Severums (Heros severus).
Though the species name means 'Severe', Severums are far from it, properly housed and fed. Given a large aquarium and passive tankmates, Severums can easily be described as mellow fellows.
My first memory of Severums was, as a very small child, I was taken to the local Optometrist, who had a large aquarium in his lobby. Soon learning of my interest in aquariums, my parents and I were invited to their home, where they had more than a dozen tanks. In a large tank, there were roughly two dozen Severums racing up and down the front glass looking at me. They were moss green with little oblong deep red spots on the flanks, and the fins were green and yellow.
I was smitten. Thus, the first larger Cichlids I kept were Severums, in the 200 gallon I bought when I was 14. Commercially bred for ages, many color variations are available, though I prefer the wild type.
A native of the northern Amazon region and small waterways in Guyana, Severums grow to a foot long, though usually slow down in growth once they reach eight inches. Naturally, they are a forest to olive green on the upper body, moving to a yellowish-green lower half. Black vertical bands are evenly spaced, starting behind the gills and ending just before the tail, though these usually fade away with age. The male has many small reticulations around his snout, and orange cheeks. Pectorals and anal fins are dark green, and the dorsal is low and speckled with chamois-colored spots.
A rather pan-shaped fish, but an attractive one in grace and character. The female is very similar in both color and size, but lacks the reticulations. Eyes are usually yellow-orange.
Severums are black and white water fishes, thus prefer soft (gh 5 or so), acid water (ph between 6.0 and 6.8), and to my experience, they are most colorful and disease resistant in it. They do best between 75 and 80 degrees. A dark substrate and background accentuates the colors of this species.
Rather shy in manner, Severums like to stay in the lower levels of the aquarium, thus tankmates should be selected that are very passive, but too large to eat. A large school of tetras that grow more than two-inches long are perfect, and they like the optimum water conditions the Severums prefer. A group of the larger Corydoras species are OK. Stay away from things like pictus cats, as the long whiskers bother the Severums when they are sleeping. Floating plants over the main swimming area usually reforms their shy nature.
The tank should be large, the larger the better. A bare minimum would be a 75 gallon for a single adult, and larger climes for a group of these charming fishes. The tank can be planted, and equipped with driftwood and caves for their security. However, if they breed, the plants around the spawning area will be torn out, because in their native waters, predators lurk in plants, so it's best to have a tank ready sans plants if you wish to breed your Severums. However, Severums rarely breed in the confines of the aquarium unless it is quite large and the fish are very mature.
Severums are normally completely peaceful, especially if kept in a group of its fellows. Only when breeding are they aggressive. They are secretive firm-surface spawners, and will use flat or rounded stones, suitably-sized caves, or overhanging driftwood to deposit the eggs. Pairs mate for life, and spawns can be quite large; in the many hundreds of eggs. Severums are fearless in protecting their spawn and fry, and will care for their youngsters for several months.
In feeding, they are omnivorous, and will take de-frosted frozen peas with the skin removed just as eagerly as they would a quality pellet or a small live shrimp. Live foods of the crustacean, annelid worm and insect larvae kind will really improve the condition and vitality of this species. Pelleted foods, including one of a vegetative nature, can round out the menu.
Variety of foods are quite important with these fish for color and development. Frozen foods are a good bet, but experiment with vegetables and different prepared foods to see what all your Severums will take. Of course, live fish are a no-no with Severums, as renal failure, followed by death, and the possibility of introducing a disease, makes feeding live fish a foolish thing.
If one has the tank space and tankmates, Severums are a good choice for a feature Cichlid species.
Our next mellow fellow hails from Central America; Hypsophrys nicaraguensis, the Nicaragua Cichlid.
A native of pristine lakes and other still bodies of water in Nicaragua and Costa Rica, this species is perhaps the most beautiful of the peaceful Cichlids in this list.
Just a grey fish when small, within a few months the youngsters will have bright blue heads and lemon yellow bodies, and soon develop a dark line interspersed by one or more large spots that runs from the gills to the base of the tail. As they grow, more and more colors, including russets, greens, and iridescent blues, present themselves. Females are the more deeply colored of the sexes, but the male grows expansive, colorful finnage, and the dorsal and tail grow flowing extensions, usually with red tips. Both male and female grow to nearly 10 inches, but she is the larger-bodied of the two. With maturity, males grow a small hump on their forehead. Mature, both male and female are spectacular fishes.
A great passive Cichlid for the large tank, your best bet to find a compatible pair is to buy eight youngsters. Because they are basically colorless when young, they are usually inexpensive, but you may have to do some searching or special order them from your local fish to secure your stock.
In a large enough tank, in the hundreds of gallons, you can keep all eight, as these Cichlids like to be in decent-sized groups, and they can make a stunning display. Otherwise, in a tank 125 gallons in size, you can transfer the best pair to it. Pairs mate for life, and though both sexes do reach 10 inches, males usually pick smaller females as their mate. These fish prefer to stay low in the bottom third of the aquarium. Soft substrates, like aquatic soils should be used with these fishes, as they like to sift though the substrate often looking for tidbits.
Cave, and occasionally substrate, spawners, Nicaragua Cichlids are one of the few species that lay non-adhesive eggs. They float just above the substrate, and the parents guard them like they are gold nuggets. They are territorial when they have eggs and fry, but I wouldn't call them aggressive. They use their size and proximity to the clutch to dissuade interlopers. Secretive spawners, if they feel their clutch is too visible to tankmates or fishkeepers, they will take the spawn in their mouths and move it to a more hidden locale.
Eggs hatch within 36 hours, and the fry are free swimming two to three days later. They can take baby brine shrimp right off, and within a week, can take the smallest pelleted foods. The fry grow rapidly, and will be an inch to an inch and a half long in a month.
The fry are difficult to sell because they are just small grey fish, but all that will change when you show the buyer the parents. Excellent parents, they will care for their youngsters for several months.
Nicaragua Cichlids can be kept in the well-planted tank with driftwood, and caves formed by flattened stones.
They like their water between pH 6.5 and 7.5, and moderately soft to moderately hard. Temperatures are 75 to 80 degrees. Only when spawning do they tear out plants, and only those very close to the spawning area, which is rather small. A gorgeous fish in the large planted tank with driftwood and stones. A dark substrate and background coupled with good and varied foods will produce a depth of color that will make them true showpieces.
In feeding they are omnivores, and unless you want them to nibble your plants, feed them peas, bits of apple and pear, and frozen foods designed for herbivores to dissuade that behavior. They like insect larvae, small crustaceans and aquatic worms, either live or frozen, though you'll get better color with live. Pelleted foods must be the highest quality for their continued health. I kept this species for 15 years before I sold them, so they are quite long-lived.
Perhaps my favorite larger Cichlid.
On to Part 3
An almost mystical Cichlid in the hobby is the Uaru (Uaru amphiacanthoides), of smaller soft waters all over the Amazon basin.
For many years known as one of the most difficult fishes to keep alive, only in the last decade or so have Uarus, sometimes called Waroos, been available commercially bred. Thus, they are much more common in shops, and adapted to aquarium life, than they used to be. In the old days, Uaru Cichlids were quite difficult to find and the vast majority available were wild-caught. These fish are extremely common in their natural range, and they serve as a food fish for the local people.
Reaching a foot long if properly kept, adult Uarus couldn't be described as colorful fish, yet they are rather pleasing to the eye. They are a greenish brown, with a long, black, oblong spot running from the gills to close to the caudal peduncle. The large eyes are deep orange. However, when breeding, both male and female are clothed in a deep velvety black, and the eyes really shine. With age, males, and to a lesser extent females, develop blue iridescence around their heads, and the male's unpaired fins form an attractive blue sheen.
Uarus are black-water fishes, that is, they do best in soft (under gH 5), acidic (pH 6.0 to 6.8) waters. They will live and very occasionally breed in more alkaline and moderately hard water, but to my experience, they live better and far longer in the soft and acid. Long-lived, as are most larger Cichlids, Uarus commonly live past 20 years properly kept.
Filtration though peat moss is quite helpful to simulate natural black waters, and a soft substrate covered with sunken Oak leaves will make your Uarus at home. Filtration must be efficient, as Uarus poorly tolerate excess Nitrate and the like, so regular partial water changes are the rule. Tankmates can be a school of larger tetras (those that grow over 2.5 inches long), larger Corydoras species and a group of the smaller, ornate sucker-mouthed catfish.
Quite passive, Uarus should be the only Cichlid species in the tank, as they are easily bullied. These fish must be kept in groups, but a larger tank (over 75 gallons) is necessary for even a pair, considering their size. Something in the range of 220 gallons would be needed to keep a group of at least six of these fishes, and you may have two pair off and spawn in your tank. The aquarium should be well-furnished with driftwood and stones, and you can plant it if you wish, but as Uarus are largely vegetarian, you'll have to satisfy their need for plant debris. The driftwood is very necessary, as the bio-film that forms on the wood is part of the Uaru natural diet.
A large, preferably planted, aquarium with much cover in the form of the driftwood and stones, and schooling Characins or calm Cypranid tankmates, will help these unusually flighty fishes to calm down, as it will be some time for them to accept your presence. They are usually quite startled by sudden lights on/lights off, and more that one Uaru has leapt out of a tank not properly covered. Planted-tank lights timed for dawn to dusk effects is very helpful. Keeping them in groups of six or more is best, as lone examples usually die from loneliness, and passive though they are, buying just a pair is ill-advised, as odds are they won't get along, and one will die, followed by the remaining fish which is now alone.
As above, Uarus do nibble plants, though some plants more than others. They usually leave Anubis species, Java Fern and Moss, alone. Swords and other large-leaved plants are usually nibbled. To my experience the nibbling isn't a problem, but that may be because I kept fresh vegetables available to them constantly. They like leafy vegetables (Romaine Lettuce, Spinach leaves, Kale), fruit (apples, pears, melons like cantaloupe, and peaches were favorites), and vegetables like frozen peas and beans. Pelleted foods containing a large percentage of greens, and frozen foods designed for herbivores, can be added to the Vegan menu. This species should be fed roughly 75 percent vegetable-based foods, and 25 percent of meaty foods like insect larvae, worms and especially crustaceans, either live or frozen. Even though they are quite shy, Uarus are very eager eaters, and are not picky about foods. A proper diet is key to keeping these fish long term.
Uarus are secretive firm-surface spawners, usually on stones, occasionally on driftwood. To my experience Uarus are always excellent parents. They lay between 200 and 500 eggs, and the female does most of the spawn tending as the male patrols the area. They are rather deliberate in their aggression when breeding. Eggs hatch within four days, and it'll be around three days before they are free-swimming. The fry feed on the sides of the parents, like Discus fry do, and can be fed baby brine shrimps the day they come up in a cloud around their parents. They grow quite fast, and will be on pelleted foods before you know it, usually in under a week.
The fry are attractively speckled with medium-brown blotches, and it'll be at least six weeks before they start to resemble their folks. One should dedicate a single large tank to breed Uarus in, as they experience a lot of stress breeding in the community tank, usually with disastrous results to their spawn.
Perhaps the most majestic of the passive Cichlids in this list are Altum Angelfish; Pterophyllum altum, of the Orinoco watershed and the northern Rio Negro.
From their native locals it is obvious these are black-water fishes, thus one should design a tank specifically for Altum Angels, as they have definite needs in the aquarium. Most available in the hobby are wild caught.
Altums require very soft, acid waters. The pH in their native waters range from 4.5 to 5.8 with near zero hardness. I kept the adults at pH 6.5, gH 2, but young fish MUST have highly acid, extremely soft waters. Without that, young Altums are very disease-prone and soon die in ill-suited conditions. When I kept them, 90 percent reverse-osmosis and de-ionized water to 10 percent tap, with the peat moss filtration, gave me pH 5.0, gH 0. The waters were so stained with tannins the single light bulb was very dim. It took six months of very slowly (via small water changes with different ratios between RO/DI and tap) raising the pH until I could plant the tank. Six years later, I sold the six to an aquarium club member who had the facilities and expertise to keep them properly. The tallest was 22 inches, the others between 16 and 18-inches tall, and between eight and nine inches, nose to tail.
Altums like their waters warm, between 78 and 85 degrees, and not for nothing is the common name the Tall Angelfish; Altums can and do grow past two feet tall, from the tip of the dorsal to the tip of the anal fin. Wild examples in nature can push close to three-feet tall. Thus, the aquarium for Altum Angels may have to be custom made, as you need to at least double the height of the adult fish for proper fin development.
On to Part 4
Filtration through peat moss is all but essential. The aquarium can be, should be, planted, for two reasons. One is the stability of established planted tanks, which Altums need, and secondly plants around the back and sides will provide a buffer, as these are easily-startled fish, dashing about the aquarium, often running into the glass and decorations, which usually results in injury, and Altums almost always die from those injuries. Floating plants to diffuse the light is helpful, as Altums dislike being exposed to the bright lighting of the planted tank.
Thus driftwood should have no sharp edges, and stones should be rounded. Altums like their aquarium rather dark, so a very dark, even jet black, substrate and background will give them security. A school of larger tetras, as many as you can safely house, will also help with keeping these fish calm. They are also a schooling fish, so six is a very bare minimum. The more Altums you can house the better your results will be, as there is comfort in numbers with these Angels.
Is all this effort worth it? They glide through the aquarium with a smooth grace and majesty that no scalare can match. They are simply beautiful in motion, and everyone who saw my adult Altums was slack-jawed awe struck. Simply a white silver with four chocolate brown bands, Altums are so different in manner than the common Angelfish it is striking, and well worth the effort in constructing a proper aquarium for these gorgeous animals.
In feeding, live food is very nearly essential, especially since you'll need it on hand if they reject prepared and frozen foods. Insect larvae, aquatic worms and small crustaceans are easily cultured, and my six-part how to culture various organisms is on the forum. I can also suggest books on the subject.
You might get them to take frozen black mosquito larvae, as the larvae are one of the Altums' favorite natural foods, if you don't want to culture live mosquito larvae. Just make sure the frozen larvae is well defrosted before feeding.
Fed live foods several times a week usually results in a spawning, which is a very special thing. Sexually mature adults usually spawn on the leaves of the big sword plants, like Echinodorus bleheri. A normal spawn is between 200 and 500 eggs. The female tends the eggs, the male patrols the area. In a large aquarium, aggression is virtually nil.
Eggs hatch in about a week, and the fry will become free swimming within another week. They will take baby brine shrimp and microworms soon after coming up in a cloud around their parents. The fry also feed a bit on the parents' sides. Altums are very usually great parents, and will guard the fry for up to three months. The fry grow fairly quickly, so you must be prepared with other live foods as they grow. Live foods mixed with small pelleted foods usually weans the fry off of live food only.
A challenging fish to keep properly, Altums aren't for the inexperienced.
An old favorite is the Firemouth Cichlid, Thorichthys meeki, a native of soft waterways in the Mexican Yucatan Peninsula, Belize, and Guatemala.
One of the long-standing popular members of the Cichlid family, Firemouths earn their common name with a deep red breast area that goes up into the mouth of the fish. Properly kept, Firemouths can be one of the most beautiful of the smaller Cichlids.
Topping out at a shade over six inches, Firemouths have greenish gold above the red, accentuated by large, distinctive scales. A broken dark line runs from the eye to tail, and a darker green gold above it. An attractive occelated black spot is low on the gill plate, and the fins are a pretty mix of red and iridescent blue. Adult males develop long extensions from the dorsal, tail, and anal fins. A downward sloping forehead gives them a bit of a dour look, but all in all, a quite attractive fish in all respects. Colors get deeper and deeper as the fish age.
Completely passive to tankmates too large to eat, a group of Firemouths is a good choice for the larger planted tank. It's best to buy a group of six or better eight youngsters if you have a tank larger than 90 gallons in size, as Firemouths males are territorial, and need the space of larger tanks to have those territories. Boundary disputes are common, and much gill flaring is seen, but I've never seen any violence in these stand-offs. A monogamous fish, Firemouths mate for life.
It is foolish to buy just a pair, since these ARE Cichlids, and the overwhelming odds are, one will not accept the other as mate, and soon one of the two will die. Groups of youngsters is the only way to find a compatible pair. With eight, the chance is over 90 percent of finding a compatible pair. Six, the chance drops under 70 percent.
By nature a cave spawner, and in every Firemouth group I've kept, they are most excellent, dedicated parents. The pair will also select a flat rook if a suitable overhanging cave isn't available. Average spawns are around 300 eggs, and both sexes share spawn tending. Eggs hatch within 72 hours, and within four days the fry are free swimming and ready to eat. They'll eagerly take live baby brine shrimp and microworms, and be on small pelleted foods a week. Firemouths are relatively aggressive when spawning, but in a large-enough aquarium, that isn't a problem, as they stay in a closed area with their brood.
Parents tend the fry and defend them against tankmates until the fry wander off on their own, usually in their fourth month.
Firemouths are adaptable as they come from shallow, often turbid, streams and rivers. Torrential rains and the dry season cycle means the fish experience drastic changes in water character during the year. They can thrive in the pH 6.5, gH 5 planted tank as well as they can the pH 7.5 moderately hard waters, say gH up to 12. They prefer their water 75 to 80 degrees, and are a true omnivore. One of the tricks to intense coloring in Firemouths is soft, fresh algae. With their downward facing mouth, Firemouths scrape algae off surfaces if you provide it for them. Algae is easily cultured on rounded stones in a sunny spot with an ammonia source, like guppies. Get the quality guppies, not the feeders, to prevent introducing disease with the algae. The upshot is algae makes Firemouths much more colorful and hardy. They can live easily more than 20 years if one respects their omnivorous nature. Firemouths will also nibble most veggies, so you may find them pushing aside Loricariads to get at say, a cucumber half. Firemouths also take most frozen and live worms, crustaceans and insect larvae, as well as quality pelleted foods, but one must be aware for best results foods that are vegetable and vegetable-based should be at least half the menu.
In nature, Firemouths are found around the shallow bank of streams and rivers between driftwood and stones, so tank decoration is obvious. You can well plant their tank as they tend to like the cover because they are rather secretive spawners, and to my experience they neither dig nor tear out plants. Firemouths prefer to stay in the lower third of the aquarium, usually just a few inches above the substrate, which should be soft, like aquatic soils. Firemouths often take a mouthful of substrate and make a chewing motion, ala Geophagan-like, searching for tidbits. A dark substrate and background will have your Firemouths compensating with deeper and more intense coloring.
Tankmates can be a school of larger Characins, like Lemon or Diamond Tetras. Fish like medium-sized Loricariads, like Bristlenose catfish, are usually ignored, but to my experience, Firemouths don't like Corydorus cats in their tank, as they roam too close to these fish, and it seems to make the Cichlids uncomfortable. Stay away from Tiger Barbs, as they nip at the Firemouth finnage. Most other Barbs are OK. Pictus cats drive Firemouths nuts with the large whiskers when they are sleeping, and they will eventually kill the Pictus because of it. They should be the only Cichlids in the aquarium for best results with this species, given the males' territorial nature and the great good looks of these fishes.
Firemouths are one of the long-standing members of the family, appearing in aquarium books in 1933. Somewhat overlooked these days, Firemouths are a good choice as a feature species in a larger aquarium.
These are a few of the most passive Cichlids you can buy. I encourage you to do in-depth research on those you're interested in.
Last edited by Dave66; 11-12-2008 at 06:51 AM.
Once again Dave, you have exceeded my expectations. I loved this primer and hope to one day have a severum. Your writings on the firemouth will help me undoubtedly. One question about feeding the firemouth. What is the best way to feed them vegetables? Let the veggies float in the tank? Slice the cucumber?
Could you also go into a little detail about how to grow the algae rocks with the guppies in the same containter? If you don't want to type this all out you can shoot me a PM instead. Thanks again Dave!
55g- blood parrots, SAE, bristlenose plecos
Dave, how do you reconcile this statement with the fact that in the wild during the rainy season, Oscars regularly feed on small fish? A properly balanced diet for an Oscar will include, fruits, veggies, nuts, insects, frozen fare like beefheart and bloodworms, as well as the occasional quality feeder fish. Feeder fish are not necessary however a good quality feeder like home bred guppies are certainly not a problem. Even predator experts like Brian Scott (Top of the Food Chain columnist for TFH) recognize the value of feeders in a natural diet for Oscars.
Originally Posted by Dave66