They Ain’t Got No Alibi: Ugly Fishes for the Home Aquarium
By Craig Sernotti
When the average hobbyists think of fish, beauty often comes to mind. From breathtaking reef dwellers to exotic wild caught African cichlids, beauty sells. But given that there are tens of thousands of fish, as well as many more waiting to be described, it shouldn’t surprise anyone that some are, well, ugly. These are the fish that only their mother’s could love.
Ugly is, of course, subjective. For this piece, an “ugly” fish as a species with a certain combination of morphology and coloration that would make your average kindergarten class give a collective “Eeeeewww!” With apologies to our parents and teachers who taught us otherwise, we will be judging these books by their covers.
Who’s to say what’s ugly? These Red-tail Catfish - Tiger Shovelnose hybrids are beautiful to some, hideous to others.
On the other hand, I’m not mentioning those controversial hybrids such parrot cichlids or balloon mollies, or fish that have been dyed. These are ugly in their own right, but we made them that way, and that’s a story for another day.
Because people are naturally drawn to attractive species -- hence the widespread availability and popularity of things like South American tetras and Rift Valley cichlids -- many of the species covered in this article will only be available on an occasional basis. However, even if it’s only “sometimes,” these losers in the looks department deserve some attention, too.
It’s fitting to start with the catfishes (order Siluriformes). After all, they’re one of the most widely distributed fish on the planet. They can be found on every continent except Antarctica and over 3000 species have been described.
Hobbyists will be most familiar with the personable Corydoras catfish and various species from the family Loricariidae, a group that includes those fish we call plecos and suckermouths. Most Corydoras rate highly on the cuteness scale, and at least some of the loricariids are downright stunning, -- the Zebra Pleco Hypancistrus zebra to name but one. Other loricariids are just plain goofy looking rather than ugly, -- the whiptails, genus Rineloricaria, for example.
Actually, there are dozens of catfish that might be considered ugly, but space limits us to just one genus, but don’t worry, it’s a doozy! It’s the genus Chaca, a group of Asian catfishes occasionally seen in the trade and known to hobbyists as Angler Catfish.
If there’s a type species for ugliness, it’s going to be one of the three species in this genus, Chaca bankanensis, Chaca burmensis or Chaca chaca. Telling them apart isn’t easy, since they all look very similar and get to about the same size. They do come from different parts of Asia though, so knowing where your fish was exported from is extremely helpful. Chaca burmensis is apparently endemic to Burma and is only rarely traded. Chaca chaca is more commonly seen, with most specimens coming from South Asia, particularly India, though it is has been reported as occurring as far east as Malaysia and Indonesia. Chaca bankanensis is a Southeast Asian species known from Malaysia, Indonesia and the island of Borneo.
Chaca catfishes get to about 8 inches (20 cm) in length and mostly sedentary, so a 30-gallon tank with robust filtration should be fine. Water circulation is important because these fish come from flowing rather than still water habitats, and the filter should be big enough it can handle the waste produced by what is fundamentally a big, predatory catfish, albeit one that doesn’t move about much.
They are gulp-and-suck predators (Finley, 2000) and belong in a specimen tank. Substrate isn’t too important, but the tank should include several hiding places. They’ll adapt to a range of water chemistry conditions, though a slightly acidic to neutral pH is ideal. Chaca accept pretty much only live, meaty foods, particularly small fishes. Indeed, some specimens will only accept live fish. If you want to keep these fish, you will likely have to breed and gut-load your own feeder fish, since feeders fish bought from pet stores are not safe to use. Avoid fat- and thiaminase-rich species such as minnows or goldfish, and instead focus on livebearers or cichlid fry. Most Chaca will take alternative live foods such as earthworms (nightcrawlers) and shrimps without complaint, and at least some hobbyists have weaned their specimens onto frozen foods and even pellets. But there are no guarantees, and this species remains difficult and expensive to feed.
A further warning must be given about these catfishes before we move on. They possess a sharp dorsal spine that can inflict a painful wound. Reports have also circulated that they seem to release a substance from their skin that can kill any other fish kept in the tank with them. Be aware of this, and house them on their own and if you do need to handle them, do so with care!
It was hard for me to decide on a cichlid for this piece, as the species I reviewed didn’t meet my criteria. But then I came across Cyphotilapia. The species in this genus may not get the “Eeeeewww!” we’re looking for, but one can argue that Cyphotilapia is an aquatic butterface -- everything’s good but ’er face. (Actually, since the males develop the bigger humps, should it perhaps be “everything’s good but his face!”).
From their pronounced jaws to their thick lips to the nuchal humps on their foreheads, Cyphotilapia will make you do a double-take. There are two described species in this genus -- Cyphotilapia frontosa and Cyphotilapia gibberosa -- and both are endemic to Lake Tanganyika. These large (about 12 to 16 inches) but lethargic schooling cichlids require equally large tanks. Males are mildly aggressive towards each other, and they are best kept in groups of a single male alongside two or more females.
A face only a mother could love? Cyphotilapia are odd-looking cichlids, but charming in their way.
They are quite easy to breed in home aquaria. If you want to spawn Cyphotilapia, then don’t include any tankmates -- they will eat the fry. Otherwise, large Julidochromis, Lamprologus, Lepidiolamprologus, and Neolamprologus cichlids make good tankmates (Scott, 2008). As with other Tanganyikan cichlids, the pH shouldn’t fall below 8.0 and the water should be hard. Decor must include several securely positioned rock caves, PVC pipe off-cuts, or flowerpots. These cichlids come from deep waters, so keep the lighting subdued.
In the wild Cyphotilapia primarily eat invertebrates, including snails and clams, and various small fish. In the home aquarium they are easily maintained on wet-frozen and pellet foods. Algae pellets in particular seem to be useful additions to their diet, promoting good health and coloration.
The family Gobiidae is another large fish family with over 2000 species. Some are real lookers, some are not. One of the most bizarre-looking of them all is the Violet (or Dragon) Goby Gobioides broussonnetii. This species comes from the tropical Western Atlantic and is something of a gentle giant.
A similar, marginally smaller species, Gobioides peruanus, comes from the Pacific coastline of Central and South America and is also traded from time to time. There’s some confusion in the hobby over which species is seen more often, and it may depend on which part of the world you’re in. North American aquarists probably see Gobioides broussonnetii most of the time, while European aquarists seem to be offered Gobioides peruanus on a fairly regular basis.
There are at least three other species, Gobioides africanus, Gobioides sagitta and Gobioides grahamae, the first two of which come from Africa and the third from Brazil. Which of this is these are traded, and how often, remains unknown. Occasionally, the very similar gobies from the Asian genus Odontamblyopus are sometimes seen.
In any case, Violet Gobies are big fish, up to 22 inches in length, though they aren’t terribly active most of the time, and single specimens can be kept in well-filtered 40- to 55- gallon systems without problems. They are territorial though, and in groups will squabble over burrows and lairs. Bear this in mind when keeping more than one specimen, and provision space and hiding places accordingly.
Violet gobies are extraordinary fish, but despite their monstrous appearance, they’re really gentle giants.
They These fish are known as Violet Gobies because of their color, particularly the purple bands on their flanks, but they live up to their other name, Dragon Gobies, when swimming about and feeding. They really do look like Chinese dragons! Live brine shrimp isn’t terribly nutritious, but it’s a great treat, and nothing gets these gobies swimming about quite so effectively.
Otherwise feed them on algae wafers, sinking pellets, wet-frozen invertebrates such as bloodworms, and occasional offerings of chopped meaty foods like clam (cockle) and squid.
Tankmates should be chosen with care. Avoid fish that will eat their food before the gobies get a chance. Surprisingly perhaps given their size, small livebearers such as guppies make ideal companions. Properly fed Violet Gobies do not eat fish, even livebearer fry. Violet Gobies must be kept in brackish water; aim for a specific gravity between SG 1.005 and 1.015. Since these are nocturnal, burrowing fish the tank should have plenty of hiding places. Ideally, provide a sandy substrate, but at the very least, ensure there are plenty of (large!) hollow ornaments. PVC tubes, perhaps siliconed onto slate to hold them in place, are very convenient.
There are several different genera of mudskipper in the subfamily Oxudercinae, but species of Periophthalmus that do best in aquaria. Mudskippers are very interesting Indo-Pacific fish that use their pectoral fins to walk on land. Yes, you read that right: mudskippers are fish that not only move about on land, they prefer to spend as much time on land as possible. In fact, they need to leave the water to feed and interact socially, so a mudskipper tank will be more like a vivarium than an aquarium.
To keep mudskippers you’ll have to set up a tank that’s half-water and half-land. The water only needs to be deep enough the mudskipper can cover its body when bathing: a couple of inches should do. Filtration needn’t be complex, and a simple air-powered sponge filter or box filter is ideal.
The water must be brackish though, around SG 1.010 being ideal, though a little higher or lower will do no harm. In fact mudskippers typically come from mangrove habitats where the salinity varies a good deal. But that said, no mudskipper can survive being kept in freshwater conditions indefinitely, whatever your retailer might suggest.
Mudskippers, such as this Periophthalmus barbarus, are not difficult to keep, provided their needs are understood first.
For the land part of the tank, use your imagination! Think of a sand bank with lots of mangrove roots, and you’ll have the right ideas. A gradual sloping bank of coral and smooth silica sand with a bit of gravel mixed in makes a good base, into which you can plant mangrove roots, bogwood, smooth pebbles and artificial plants. PVC pipes can be stuck into the sand here and there to create burrows.
The tank must be heated, and critically, it should have a secure lid. Partly this is to keep the air temperature and the humidity in the tank nice and high, but it is also to stop the mudskippers from escaping (which, as climbing, walking fish they are very good at).
Mudskippers are territorial and don’t necessarily work well in groups. The species most commonly sold in the US appears to be Periophthalmus barbarus, a notoriously aggressive species to the degree that males inevitably end up being kept alone. This large species (to 10 inches) has brilliant blue colors on its dorsal fins, and is the only species from West Africa, hence its common name, the West African Mudskipper.
The Asian species are somewhat less aggressive depending on their size, with the small, to 2 inches long, Indian Dwarf Mudskipper (probably Periophthalmus novemradiatus) doing quite well in groups. A certain amount of overcrowding can help with mudskippers since this prevents any one specimen from becoming undisputed master of the tank, but as ever, employ such methods cautiously.
The Silver Barred Mudskipper Periophthalmus argentilineatus is somewhere between the two extremes, being less easy-going than the Indian Dwarf, but not quite so psychotic as the West African Mudskipper.
On the whole mudskippers are best kept on their own. Mudskippers are also voracious as well as opportunistic hunters, and besides their preferred diet of worms, insects, and crustaceans, they will readily go after smaller tankmates, including fish and fiddler crabs. Conversely, bigger fish scare mudskippers, who presumably consider them predators, and the mudskippers avoid going into the water, which doesn’t do much for their health.
The limited size of the water-filled area is another restriction. If you have the space, then tankmates of similar size, such as Sailfin Mollies (Poecilia latipinna) or Knight Gobies (Stigmatogobius sadanundio) are possibilities, but most fishkeepers end up keeping their mudskippers alone.
Mudskippers accept a wide variety of commercial and live foods, both meaty and plant-based, so you shouldn’t have any trouble feeding them.
Here now are two fish that are or aren’t gobies, depending on your taxonomic point of view. They are sleeper gobies, and while members of the goby suborder Gobioidei, they are members of a distinct family known as the sleeper gobies, Eleotridae, rather than the “true” goby family Gobiidae (Sterba, 1973).
The Marble Sleeper Goby is one of the largest gobies, and in Southeast Asia widely considered excellent eating.
The first fish, Oxyeleotris marmoratus, is an Asian species known commonly as the Marble Goby. It is one of largest of all the sleeper gobies, and indeed goby-like fishes generally. It gets to about 24 inches in length, so if you are considering a specimen, be certain you have a large enough tank with plenty of filtration.
Oxyeleotris marmoratus is a fascinating fish with a sinister, if rather nicely marked, appearances. It will accept a wide variety of meaty foods -- start with earthworms and go from there.! Oxyeleotris marmoratus is a hardy, mostly nocturnal fish that will accept most water conditions and does well in both fresh and brackish water conditions. Tankmates are not recommended, as this species is somewhat territorial as well as highly predatory.
In the wild Oxyeleotris marmoratus is a burrower, and these gobies may also take to rearranging the tank’s decor. Make sure all structures are secure and won’t fall down. Bogwood and large rocks are a good, safe choice. Oxyeleotris marmoratus requires hiding spaces and plenty of shade.
The Crazyfish Butis butis is a predatory, medium-sized brackish water sleeper goby that does well kept in community tanks alongside fish too large to swallow whole.
The second species, Butis butis, is commonly called the Duckbill Sleeper or Crazyfish. This latter name comes from its habit of swimming sideways and upside down. It’s an Indo-West Pacific fish that grows to about 6 inches, is highly predatory, has a very large mouth, and can tolerate varying levels of salinity from freshwater through to fully marine conditions. Under aquarium conditions it does best in hard, slightly brackish water, around SG 1.005.
Butis butis will ignore any fish it can’t swallow, but anything it can get into its mouth is fair game. Live foods may be used initially, particularly things like earthworms and river shrimps. But this species will eventually take wet-frozen foods without complaint, particularly if offered enticingly using needle-nose forceps. Offer things like squid, prawn, and white fish. Be sure to include lots of large rocks and bogwood to create the necessary overhangs and caves this species likes to use as hiding places.
Like catfishes, loaches are often dismissed as mere bottom-dwelling scavengers. Not so! These fishes are interesting aquarium specimens, especially when placed in a biotope tank that allows you to observe their natural behaviors.
Many are quite attractive fish, -- the much loved Clown Loach for example ,-- but one at the other end of the spectrum is the Mooseface Loach, Somileptus gongota. This is a shy, nocturnal loach from India, Bangladesh, and Nepal that reaches a length of about 5 inches.
A sandy substrate is a must, as the mooseface will burrow for cover when alarmed. You will also need a strong, tight aquarium top to prevent jumping if spooked. This species does well in groups of at least three. Somileptus gongota can be kept in a community tank with other quiet fish, such as non-nippy tetras and peaceful loaches, such as kuhli loaches (Pangio spp.). Water chemistry isn’t critical, but ideally the water should be soft to moderately hard and the pH slightly acidic to neutral.
Feeding Somileptus gongota won’t be a problem. It readily accepts small live and wet frozen foods, and eventually adapts to taking good quality pellet and wafer foods.
To me, there’s something eerie about a colorless, eyeless fish gliding through the water. Blind fishes are usually found in caves and have adapted to living in complete darkness. Blindness and lack of body pigmentation isn’t limited to one fish type of fish, including catfish, characins, cichlids, gobies, even a blind molly. Though well known as scientific curiosities, most exist in small populations and are in many cases endangered species. Few are traded as aquarium fish, save one, the Blind Cave Tetra Astyanax mexicanus, a species that has proven to be both hardy and easy to breed.
This fish is essentially a variety of Mexican Tetra (also Astyanax mexicanus) and maintenance of the two species is very similar. Moderately hard, slightly basic water at a middling temperature is recommended; aim for a pH between 7-8, hardness above 10 degrees dH, and a temperature between 72-75 degrees F (22-24 degrees C). The Blind Cave Tetra is normally kept in a group of six or more specimens in a 30-gallon tank. Lighting should be subdued, either simply not illuminated or else provided with floating plants that produce lots of shade.
Blind Cave Fish are best kept in groups on their own in a cave-themed aquarium.
Two other uglies for your consideration…
Though rarely traded, the Bengal Tongue Sole Cynoglossus cynoglossus is an interesting if usual-looking fish for the advanced aquarist. Despite its name it comes from a much wider area than simply the Bengal region of India, can be found in estuaries across much of the Indo-West Pacific region. These are difficult fish to keep, in part because they only eat live or wet-frozen foods and aren’t very good at competing with other bottom feeders. But they are also brackish water to marine fish, and won’t last long in a freshwater tank, despite often being sold as freshwater fish.
Several other Cynoglossus species are sold, some freshwater, others brackish/marine fish. Unless you know otherwise, they’re best kept in slightly brackish water, around SG 1.003 to 1.005, until you can positively identify the species either way. This will be enough salinity to ensure the brackish water fish stay healthy, but not so saline that freshwater species would be stressed.
Basic care is similar to other soles and flounders. The tank should have a soft sand substrate, a mixture of smooth silica sand and coral sand being ideal, and lots of open space for swimming. Keep rocks and other decorations to the edges of the tank. Cynoglossus cynoglossus gets to about 8 inches in length, so the tank must be appropriately sized.
This South American Wolf Fish Hoplias malabaricus is the most widely traded member of a group of large, predatory fish known to scientists as the family Erythrinidae. Although definitely somewhere on the ugly scale, it’s a fish that will no doubt appeal to fans of large predatory fish.
If you want to keep a Wolf Fish, you’ll need a large aquarium. Aquarium specimens will grow to more than 20 inches in length given good conditions. It’s recommended you skip keeping juveniles in smaller tanks, and go straight on to keeping your specimen in a 125-gallon system that will provide plenty of grow-out room. A big tank will also ensure good water quality, these fish being somewhat more sensitive to environmental conditions than its ecology in the wild might suggest. In its natural habitat these fish are air-breathers able to thrive in swamps where most other fish cannot, but in captivity they do not tolerate such conditions continuously, and have to be provided with a generous, well-established biological filter. Large, regular water changes are a must. Water chemistry isn’t critical, but should be on the neutral to slightly acidic, not too hard side.
The Wolf Fish is a big beast with lots of personality, but a bad attitude and an appetite to match!
Make sure your tank also comes with a strong, lockable top. Numerous hobbyists have reported that their wolves have tried to jump out of their tanks, often hitting the lid with considerable force, enough to open a lid that isn’t securely closed.
Forget about tankmates; the Wolf Fish is both territorial and an extremely powerful nocturnal predator. Limit decoration to robust plants such as Amazon swords and giant Vallisneria. Use some large bogwood roots to build hiding places. Feeding is not particularly difficult as these fish can be trained to take frozen seafood and pieces of white fish. But initially you will need to offer some suitable live foods, particularly things like earthworms and river shrimps. Wolf Fish will of course eat small fish, but as always, don’t use store-bought feeder fish and avoid species with a high thiaminase and fat content, such as minnows and goldfish. Gut-loaded livebearers and juvenile cichlids would make better choices.
The Wolf Fish has been bred in aquaria. Pairs should be of an equal size, as courtship involves vigorous wrestling (Azuma, 2002). If a smaller female tires, she’ll be attacked. After courtship, the female deposits her eggs and they’re fertilized by the male. The female should then be removed for her own safety. The male guards the eggs and fans them until they hatch -- about two days (Azuma, 2002). Offer the fry small live foods such as microworms, daphnia, and newly hatched brine shrimp. Larger fry may cannibalize their smaller siblings (Azuma, 2002).
Fish aren’t all brilliant blues and striking iridescence. They aren’t all streamlined by Nature or bred for fancy fins. Some give true meaning to the word different -- in this case a polite way of saying they’re ugly. But again, beauty’s in the eye of the beholder!
Hopefully this article has piqued your interest and introduced you to a few species that you previously weren’t aware of. If you truly want something different have the opportunity to keep them, give these fishes a chance! And for the record, I don’t think any of them are ugly. Except Cyphotilapia. But then again, I prefer catfishes!
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Scott, B. “Cyphotilapia: Deep-Water Piscivores of Lake Tanganyika.” Tropical Fish Hobbyist (May 2008). pp. 54-56.
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Wood, K. 2007. Adventure Aquarist Guide™: The 101 Best Tropical Fishes. Microcosm/T.F.H Professional Series.
Useful web sites
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