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Otopharynx lithobates (Oliver, 1989): Lithophiles from Lake Malawi
|Par Scott Schwerdtfeger, 2002.|
The Lake Malawi Rock Dwelling Aulonocara "Chitande" Species Group
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My decision to either acquire or breed Otopharynx lithobates was actually rather serendipitous. I had seen the name in my regular perusals of Tropical Fish Hobbyist, Online Articles on Cichlids, and frankly, in anything I could get my hands on that pertained to these miraculous marvels, these fascinating fish from Africa's Rift Lakes dubbed Cichlids. I am one of those Cichlid addicts who is in love with the binomial nomenclature of it all; to me a fish's latin name is equally as important as any flamboyant morphological feature or anomalous secondary sexual characteristic it may possess. That is not to say that I am not easily swayed by a fish's aesthetic offerings: metallic coloring, diamond-patterning, elaborate fins, etc. It didn't hurt that O. lithobates "Yellow Blaze", the trade name given to the fish by my breeder extraordinaire, Allan Bliven, was a deep azure fish with a radiant yellow blaze extending from its upper lip to upper tip of the caudal fin.
But most of all, it was the semantics, the simple sound of the fish's name. I found myself repeating it interminably for no apparent reason. Oh*to*fair*inks lith*aw*buh*teez, Oh*to*fair*inks* lith*aw*buh*teez, I droned over and over. Then some nameless source at an anonymous cichlid supplier on the East Coast informed me that the fish's name was actually pronounced: Oh*tow*fair*inks litho*baits. Suffice to say, I've never been more disappointed in my life by a revisionist pronunciation of a Cichlid's name. This is just the sort of incident which characterizes, in microcosm, the whole nomenclatural mess that exists with Cichlids today. Most of the time even when people know the scientific name for a fish, they rarely pronounce it correctly. It appears the diligent study of Latin and Greek roots has fallen by the wayside (unless you're an attorney). Not that I am any more linguistically exact. I still today amiably refer to the "Yellow Blaze" Otopharynx lithobates as Oh*tow*fair*inks lith*aw*buh*teez
Incidentally, the name Lithobates comes etymologically from the Latin Lithos, meaning rock, and invokes their propensity for living and foraging primarily in caves and amongst the rocks in Lake Malawi. The name seems as apt as any since O. lithobates appears to display the same affinity for the cave structures and rocks in my breeding tank as it does for their wild counterparts. Yes, these diminutive rock-dwellers are truly Lithophiles, or "Rock Lovers." At first I found this fish's reticence and reclusive nature strange. Why weren"t they gregariously swimming up to the glass and begging for attention like my Pseudotropheus or Aulonocara?
Since I abhor an information vacuum, I returned once again to the myriad indices of my formidable Cichlid Library for some much-needed clarification on O. lithobates. A hunch told me that yet another ichthyological epiphany awaited. After a modicum of internet research and a sound scouring of my Cichlid tomes, I discovered the simple answer. These fish are rock-dwellers; that's what they do. Hence the name Lithobates. Apparently my expectations of O. lithobates behavior were wholly inconsistent with the fish's demeanor in Lake Malawi. This is the importance of culling as much information as possible on a particular species before attempting to breed it. At least now I won't be expecting O. lithobates to patrol the tank at mid-water in search of prey like Champsochromis caeruleus or Exochromis anagenys.
My O. lithobates breeding group arrived via Southwest Airlines Cargo to San Diego's Lindbergh Field from Cichlid Lovers, a peerless purveyor of fine African Cichlids out of Tuscon, Az. The owner is Mr. Allan Bliven. Allan is a breeder and wholesaler of African Cichlids with twenty years in the trade. His sage advice and personalized customer service have proved invaluable to my zealous pursuit of the Cichlid Hobby. Fish are usually FO (wild) or no further removed from wild than F3 or so. This means you don't get burned-out strains of fish which have begun to lose their characteristic wild features. I mean why start breeding with a fish whose stripes and bars are fading and whose color pales in comparison to its wild counterpart?
I do believe that every upstanding Cichlid Hobbyist/Breeder should do his/her best to ensure the perennial beauty and pristine characteristics of the species they breed. It's a sort of Hippocratic Oath for Breeders: "Don't ever adulterate or diminish the natural attributes of a fish, unless the aim is to ultimately imbue the fish with attributes of an even more desirable variety." After all, Aulonocara rubescens was created in just this way. The last I checked, there wasn't a surplus of "Ruben Reds" flocking the waters off of Namalenje Island. Still, I must say I do enjoy the contrast of a crimson peacock in there with all of those blue hues. Variety is the spice of life. But for now I shall confine our discussion to the singular subject of our lithophilic (stone/rock-loving) friends from the littoral zone, O. lithobates.
The cost to procure the fish was reasonable at about $40.00 to transport a 20 lb. box or two via air freight to San Diego. After acclimating them to my tanks, I placed them in the breeding tank. The male had already developed the characteristic yellow blaze on the dorsal fin and face. The females were a dull brown color with intermittent black spots, and only a thin stripe of yellow visible at the highlight of the dorsal fin (see photos). I remarked at the time that the male bore an uncanny resemblance to Sciaenochromis fryeri with a flaming yellow mohawk. Still the protruding eyes and torpedoesque shape distinguished this fish from the famed "Electric Blue." It's sometimes difficult to resist the temptation to do a comparative anatomical analysis of all fish with quasi-similar characteristics. The relatively recent evolution of these fascinating fish is so often evidenced by their sharing strikingly similar features (e.g. a thick black line across the top of the body above the lateral line), hinting at a possible common ancestor in the not so distant past.
Top to bottom, left to right; O. lithobates male displays dominance; A brooding female ensconced in the breeding cave; The male patrols the breeding cave; A brooding female shows some dorsal; O. lithobates needs extensive caves to proliferate; O. lithobates males and females coexist harmoniously; A brooding female seeks refuge in the rocks; These O. Lithobates fry do not have to fear predators; Female O. lithobates loitering around the breeding cave. Photos by Scott Schwerdtfeger.
All I knew was that these specimens were nice and healthy, which bode well for procreative success. There were no concave stomachs, lacerated fins, cotton balls, Hemorrhagic Septicemia, or any of the tell-tale signs of diseased fish here. I highly recommend a meticulous examination of all fish when they first arrive from the breeder. Typically at least a few will need to be quarantined and treated for their symptoms before introduction into the breeding tank. In particular, you should scrutinize the fins, eyes, scales, and anal pore of the fish, as these tend to be the regions where the symptoms of bacterial or viral infections typically manifest. I prefer to maintain a special tank dedicated to this purpose. A small, 10 gallon tank is ideal. Smaller volumes of water are far easier, not to mention cheaper, to medicate than larger ones. If you've ever tried to Clout a 200 gallon tank, you know what I'm talking about. Whether the medication is anti-protozoan, anti-bacterial, or anti-viral, the price is usually exorbitant. I mean why is it that tetracycline for fish is more expensive than tetracycline for humans?
The dimensions of the breeding tank are 48"by 14" by 16". It's the epitome of the standard four-foot glass tank, which typically holds between 50 and 60 gallons, in my case closer to the former. I find that long, rectangular tanks which maximize bottom area are optimum for African Cichlids, since inordinately large periods of time are spent at or near the bottom (or at least it seems like most of the Rift Lake specimens I keep do). Tall tanks or show tanks are to be avoided as they sacrifice bottom real estate for ostentatious vertical runs. I notice my cichlids seem trapped by horizontal runs of less that 36" (3 feet.) I also like to load my tanks to keep my fish at high population densities. This reduces casualties due to aggression and imitates their natural environs (in most cases.) In order to achieve this, it's preferable to have more bottom space since the fish must share the limited nooks and crannies in the rocky substrate. The problem is not so acute with Utaka and other nektonic predators, but it profoundly affects Mbuna and rock-dwelling lithophiles such as O. lithobates. These fish are territorial when it comes to the limited number of fissures, creases, and caves in the rocks, making the construction of labyrinthine caves and hiding places of paramount importance to their success and psychological health.
I use lava rock and lace rock as my primary building blocks for caves. I usually stack the rock so as to create cavernous spaces as well as small crevices between the rocks. One technique is to stack the rock up the back of the tank. I tend to shy away from this design as it makes it difficult to divine the location of dead fish, brooding mothers, etc,. Also, detritus and waste tend to accumulate in the spaces between the rocks and the back of the tank, resulting in chronically dirty water. It's usually not until you dismantle these rocks that large quantities of detritus and excrement burst forth, revealing the source of your mysterious contaminants. I circumvent this Latent Contaminant Syndrome (LCS) by erecting the caves down the center of the tank near the bottom. To supplement your lava rock caves, I recommend the use of rock-shaped breeding caves, ceramic breeding pots, or just plain-old, dilapidated dishware. My wife likes to adorn our tanks with various and sundry pieces of old china, spice rack accoutrements, and chicken-shaped napkin rings. Hey, whatever floats your boat. The point is that having plenty caves and hiding places increases the chances of keeping your fish alive and coexisting harmoniously.
As a substrate I use Coral Sand, which is primarily Calcium Carbonate, which acts as a great PH buffer. It's a relatively fine grain sand so that most Africans can sift through the substrate as they are so fond of doing. Aulonocara (Peacocks) and Cyrtocara moorii seem to relish this pastime. In the lake, the latter actually follows Lethrinops and other substrate feeders along as they dig and opportunistically snag anything overlooked. O. lithobates seems to prefer caves to open sandy areas, although like most Africans it is penchant to a proboscis dip into the substrate, only to blow the coral sand back out onto the lava rock. If you're like me, you'll enjoy these instinctual efforts to landscape the substrate of the tank. As far as water chemistry, I am fortunate that San Diego tap water flows forth from the spigot at a near-perfect 7.5 on the PH scale. This means that further PH modification is superfluous. Nevertheless, I do add supplements to my water which I will discuss in more detail later.
I use Seachem PrimeTM as my primary water conditioner. It is a sulphureous product which removes ammonia and de-nitrifies effectively in small quantities per gallon. You can't really overdo it, and it's a great emergency treatment when you discover a week-old fish carcass festering away in your tank. You simply add 2-5 times the normal dose until such time as a partial water change is convenient. This will at least render any harmful nitrogenous waste products inert. I cycled the breeding tank for about a week before adding the O. lithobates. As an additional precaution, I added nitrifying bacteria in a bottle initially to jump start the cycling process.
Lately, I have been impressed by Tropical Science Aquarium Products. I buy them at a local warehouse-style aquatic supplier. Cichlid GroTM, a product which synthesizes actual salt compounds from the Rift Lakes and reproduces them in a bottle, is used as an additional water conditioner. I also add Spawn-AidTM, a product which utilizes the power of amino acids as the building blocks of proteins to induce spawning, the idea being that if the requisite amino acids are available in the water, spawning will be triggered. I supply Pantothenic Acid and Vitamin B12 to the fish through an infusion (pouring it in the tank) of Tetra's Cichlid VitalTM. My fish seem to enjoy swimming up and ingesting the liquid as soon as it enters the tank, almost as if it provides some sort of instantaneous nutriment (either that or they think it's food!) Aqua FlourishTM, again by Tropical Science, contains antioxidants which decimate dangerous free radicals which can slowly wear a fish's immune system down by sheer attrition. I occasionally add Rift Lake Cichlid SaltsTM, a product developed by the folks up at The Cichlid Exchange in Portland, Oregon. In addition to coagulating conspicuously on my black filter boxes, it further imitates the salinity of the Rift Lakes. This list may seem excessive, but the results thus far look promising. Keep in mind that many of these products require only a one-time "seeding" of the water. You only have to add them again at water changes.
For filtration I use a combination of the Penguin 280TM and the Aqua Clear 300TM. The penguin is a superior biological filter with a slower flow rate. Penguin's patented Bio-Wheel keeps beneficial bacteria and organisms "cultured" in its porous pleats. In contrast, The Aqua Clear is a higher flow box filter with a somewhat less effective physical filter. Each is advertised as flowing around 300 gallons per hour. I find when it comes to filtration, more is better. This is because Cichlids are accustomed to well-oxygenated water which is in constant supply in the lake. If you've ever witnessed the jubilant celebrations that occur when you make those much-needed water changes, you know the power of fresh, well-filtered water. The more filtration you have, the more you can load up the tank, as filtration on a massive scale is needed to process the considerable amounts of waste and bio load generated by such dense populations in the aquarium. Current is another key element to my breeding tanks. Powerheads keep the water flowing and stir detritus up into the water column where it can be processed by your filters. I do recommend that you remove the activated carbon elements from any filters when you notice females carrying eggs. Excessive amounts of carbon filtration has been known to produce "sliders", or fry which are born deformed or deceased due to a lack of important trace minerals and chemicals which have been removed by the carbon. An easy way remedy this dilemma is to remove the brooding female from the community tank and place her in a maternity tank which does not employ carbon filtration.
For this application I use the Rio 1100TM Power head, which moves an additional 382 gallons per hour of water. It also conveniently doubles as an oxygenator/bubbler. I haven't met a cichlid yet that didn't like to swim against the current of a Rio powerhead lavishing itself in the fusillade of tiny bubbles. Powerheads also have the added benefit of coercing the fish into swimming. The fish are not afforded the luxury of stangnacy. This translates into increased exercise and health. More liberal feeding is another option afforded by a strong current in the tank. In emergencies, the fish can duck into the rock caves on the bottom to escape the relentless flow of water. Increased current actually increases the perceived (by the fish) gallonage of your tank. For instance, if a fish would reach a given size in a 40 gallon tank with no current, he would achieve a proportionately larger size with the powerhead and current.
When necessary, I heat the breeding tank with an Ebo JagerTM 150 watt model TS. I find these to be high quality and consistent in terms of temperature maintenance within a few degrees. I keep the tank between 77 and 78 degrees farenheit. The tank décor is simple and spartan. I have a Penn-Plax Vegetation theme backing on the tank. A few plastic vallisneria plants punctuate the bottom at intervals, and that's about it. The lighting comes courtesy of twin 48" Fluorescent Aquarium tubes. One is a generic aquarium bulb whose wavelength is red spectrum; the other is a specialized Actinic bulb designed to accentuate the blue spectrum and give the water a decidedly tropical look. O. lithobates, in particular the male, looks positively luminescent beneath Actinic lighting. The room in which the breeding tank is located also receives a small amount of legitimate sunlight during the day as well.
I religiously maintain the filters, changing the activated carbon elements at recommended intervals. The gradual accretion of waste, algae, and unconsumed food can and will significantly reduce the efficiency of any filter. I give the breeding tank 50% water changes every 2-3 weeks. I try to alternate filter cleanings with water changes whenever possible. This way you avoid "shocking" the fish by eradicating too much of their original, bacteriologically cultured water. Under these conditions I have bred O. lithobates as well as a few other species, successfully. It may surprise you to discover that I do this all in a multi-species community tank, opting not to isolate O. lithobates and its fellow conspecifics in a solitary breeding tank.
The denizens of my breeding tank are the single male O. lithobates "Yellow Blaze," which according to Konings is a morph of O. lithobates found in the area around in the southern part of Lake Malawi, near Zimbawe rock, or possibly Chinyamwezi Island. His harem originally consisted of three female O. lithobates . Unfortunately, one of the females "expired" soon after my breeding experiment began. There is a juvenile Cyphotilapia Frontosa (Mpimbwe Blue) in the tank as well. He is languid, mild-mannered, and generally unobtrusive, and thus poses no aggressive threat to other tankmates. It could be said that he goes with the flow (of a Rio 1100.) The small, shell-dwelling Neolamprologine Lamprologus ornatipinnis can be seen resting gently on the bottom from time to time. I had to rescue him from a bloodthirsty Boulengerie who nearly consumed his tail in its entirety. A small breeding group of Aulonocara "German Red" share the environs. The peacocks too have carved a niche in the rocks in which to scour the substrate for invertebrates. Rounding out the tank is good old Hypostomus plecostomus, presumably for domestic purposes (algae abatement) even though as Plecostomii get larger, they tend to get lazy and lead slothful lifestyles thereafter.
My reasoning for choosing a community in which to breed O. lithobates is that the fish appear at ease in this environment, not to mention the fact that I, like most hobbyists, have to utilize all of my available tank space frugally. I am sad to say that I suffer severely from Multiple Tank Syndrome (M.T.S.) the compulsive need to continuously buy more tanks with the justification: "I don't have enough tank space, therefore I need another 75 gallon." The real solution here is to cease buying and amassing new fish, and you won't need to buy new tanks. Despite my lucid understanding of this principle, something goads me on to impulsively order up more fish than I can accommodate, thereby necessitating the purchase of more tanks! It's like a vicious cycle. Judging from the number of tanks perennially for sale in newspapers, bargain periodicals, and local classified ads, etc. M.T.S. is a fairly common affliction affecting thousands of aquarists annually. The final stages of this progressive disease include liquidating most if not all of your tanks for little to no money in order to simplify a move. More on this later.
From what I have observed, O. lithobates is a prolific fish which needs only the minimal amenities to be induced to spawn. I feed the fish a combination of Super Red Color Enhanced flake, Hikari Gold pellets (Red), Spirulina Pellets, Tetra Freeze-Dried Krill, Bloodworms, Beef Heart, and a few other carnivorous delights on special occasions. All fish need a healthy dose of pure protein every once in a while! The key with diet for O. lithobates, or for any Cichlid for that matter, is variety. O. lithobates is a substrate scavenger that even feeds on the nutrient-rich excrement of other herbivorous/omnivorous fish. As such, I feed them predominantly Spirulina pellets (some purists insist on an all-flake diet) and flake, with only an occasional meat treat. Like most Africans, O. lithobates quickly adapts to aquarium foods and will eat most anything I throw in there.
I happen to subscribe to the school of thought that dictates liberal and frequent feedings. Some breeders/suppliers feed their fish the absolute minimum to avoid filters clogging and high feed costs, but intrepid hobbyists, unconstrained by such concerns as massive overhead, would do well to splurge and fatten their breeders up. They will grow rapidly, and reward the patient hobbyist with abundant clutches of fry. While this road leads to quick growth and reproductive health, it also leads to more frequent water changes and increased filter maintenance. Everything in life's a trade-off; it just depends how much time you're willing to invest in the trade-off. At any rate, your cichlids should always appear hungry, whether they are or not. O. lithobates have moderate eating habits and are nowhere near the pigs that Protomelas or Pseudotropheus are. Whenever possible it is prudent to observe the breeding tank uninterrupted for 20-60 minutes to assess many factors. Some of these include: monitoring to see if fish have died, checking to see if spawning has begun, checking water quality, etc. Close scrutiny of the breeding tank pays dividends in the long run, especially quick rise in ammonia concentrations can have expensive repercussions. (i.e. losing all your fish to the tune of hundreds of dollars)
I find that O. lithobates possesses a generally shy and retiring affect, preferring to dwell in the rocks and observe rather than swim freely about the water column. The male displays more audacity when it comes to confronting me or spending extended periods of time at the front of the tank. Aside from chasing the females around the tank skittishly, he tolerates them for the most part. Sometimes the male will even congregate with the females and frolick in the rocks with them. Nevertheless, it is patently clear to all that he is in charge.
Photographing the breeding tank was difficult at first, but after 30 minutes or so of sitting there pointing the Nikon at the glass, O. lithobates became curious and both the male and his attendant mini-harem emerged to give me a show of lithophilic (rock-loving) solidarity. I could almost swear that they were all vying with each other for the camera's attention. Such gregarious and extroverted animals these Cichlids are! Although the male has colored up considerably since I purchased him, I am still not sure whether this O. lithobates really puts on a breeding dress. I have noticed a nuance in the markings of the females while they are brooding. They tend to lighten way up and assume an almost purely silver look, the black splotching and usual brown tint tending to fade from sight. Currently one female is brooding while the other one runs interference for her. You will note her frequent presence in the photographs of the breeding tank. I have observed the non-brooding female initiating spawning rituals with the male herself recently
I was a bit taken aback by the reclusive nature of O. lithobates initially, thinking that perhaps the fish had been unduly raumatized on the plane flight to San Diego. In truth, O. lithobates is a lithophile (rock lover) extraordinaire. This explains their rare appearances and compulsive need to hide themselves in caves and fissures. I use the stare-down technique to draw the fish out of seclusion for photo opportunities. If I simply look directly at O. lithobates ensconced in the rocks for extended periods of time, the fish tends to slowly emerge out of sheer curiosity. Their eyes are disproportionately large in comparison to their overall head size. This feature is particularly pronounced in females. They say the eyes are windows to the soul. If this is true, one might say that its enlarged orbs give O. lithobates a profoundly pensive look, as if it has already discovered the meaning of life, and is simply waiting for you to follow suite. This fact, coupled with the fish's propensity to flee from sight when someone enters the room, gives O. lithobates a sense of vulnerability. Despite this veneer of weakness, O. lithobates is a hearty cichlid which thrives in the aquarium. All in all O. lithobates offers physical attractiveness, a relatively placid temperament, and an eccentric personality. These little lithophiles make a fine addition to almost any African or Malawi Cichlid tank.
With all this talk of lithophiles and rock-dwellers, it probably comes as no surprise that rocks and caves play a central role in the courtship rituals of O. lithobates . In the case of my breeding tank, the male quickly gravitates toward one cave in the center of the tank and stakes his claim. I frequently observe him swimming in and out of this cave and gyrating his body. This is presumably to display his dominance and attract females to what appears to be a rudimentary nest of some kind in the rocks. The female O. lithobates are content to stay outside the cave and watch. Intermittently, a female will attempt to push the male through to the other side of the cave and swim through herself. These attempts are usually thwarted by the male flagellating his body and tail violently back and forth. The male O. lithobates sometimes spends minutes in the rocks. The spawning ritual has begun. As things heat up, The male enters the cave and begins swimming in circles around the rocks, passing repeatedly through the spawning cave. The female follows, apparently chasing the male's tail. The ritual dance persists until the pair settles down in the bottom of the cave where the female lays the eggs, making sure to expediently gather them up into her mouth. More frenetic circling leads to ingestion of the male's milt by the female which consummates the ritual.
Males and females of O. lithobates continue to fraternize after spawning and appear to have a tightly-knit filial bond. The mother will usually find an unobtrusive location in the rocks to quietly fan her developing fry. Along with the bloated or distended look of the female's throat which indicates the presence of young, the exasperated fanning motion of the operculum is another tell-tale sign a female is brooding. Look for these indicators, because when O. lithobates initiates spawning, it is quite prolific. At one point it seemed the females in the breeding tank were trading off having clutches. I guess this fecundity is the reason for O. lithobates' relatively reasonable price tag.
While there is often minimal risk attendant with leaving mouthbrooding mothers in the breeding tank, I prefer to remove them after fertilization has occurred, and place them in an isolated maternity tank. I do this for a host of reasons. Firstly, I have experienced instances in which other voracious tankmates have actually tried to eat through the distended throat of the mouthbrooding female to get the developing fry inside. Typical symptoms of this phenomenon are a laceration or flap of loose skin (hole) in the throat area of the female, excessive aggression by one fish in particular against the female, etc,. These activities should be considered red flags to the vigilant aquarist, cueing him or her to immediately remove the brooding mother to the safety of another tank. In this manner, the female can finish mouthbrooding in a stress-free environment. Secondly, sequestering brooding females also facilitates the stripping or removal of the fry from the mother's mouth. Lastly, it allows you to leave the fry in the maternity tank after the mother has released them to forage, eliminating the need to strip her altogether. As with most things in life, it's nice to have more options rather than less. This is especially true when it comes to tedious operations such as the handling of fledgling fry.
The primary goal of my O. lithobates breeding tank is to bring as many of the fry to maturity as possible. To achieve this every possible contingency against loss must be exercised. One such plan is leaving the brooding females in the breeding tank indefinitely. In my case, I left the female in the tank until she was perhaps a week from releasing the fry for the first time, and then proceeded to transfer her to a maternity tank. Since I was not pressed for time and could afford to let her wean her fry naturally, I opted not to strip her. Sometimes an overprotective mother will continue to guard her fry in her mouth. In these cases I do advise stripping the mother and returning the female to the community tank.
Fortunately, my female O. lithobates coughed up her young and left them to fend for themselves. At that point I went to plan C, netting the mother and returning her to the breeding tank. The fry remained in one of my innovative plastic sweater container 8.5 gallon maternity tanks. I found them at a place called The Container Store for $5.00 a piece. They came complete with lids which were easily customized to fit any set-up. Ironically, they turned out to be just the thing for nascent fry. That's the beauty of small fish; they occupy such negligible amounts of tank space. But alas, all fish must grow. That's where superior fry care comes into play.
I set up the fry tank using the trusty plastic sweater container (See Photo), a small quantity of coral sand as substrate, a sponge filter, an Ebo JagerTM 50 Watt heater, and a quick blast of bacteria in a bottle. The advantage of a sponge filter is that the fry can feed off the algae growing on it. In addition, there are no lethal intake grates which inevitably suck up your fry and trap them, kill them, or worse. Mechanical filters may be used provided the intake tube end is shrouded in a sponge element or small piece of panty hose. I arranged a few lava rocks just to afford the fry some nooks and crannies in which to hide. The more hiding places, the better. I placed two plastic plants in for good measure. The fry seek refuge wherever they can and the battle to establish the tank hierachy begins. O. lithobates was able to eat finely crushed flake almost immediately. Fry Bites, a powdered formula, is also a good choice for fledgling fry. Basically, you just have to make sure your food is ground up finely enough to where the fry can easily consume it.
With no chemical (charcoal) filtration in my O. lithobates maternity/fry tank, frequent water changes were necessary to keep O. lithobates. Some contend that frequent partial water changes are simply not necessary. For a brief time in my youth I almost lent creedence to such theories, before my empirical observations of Cichlids in captivity persuaded me otherwise. As water quality decreases, there is a proportional decrease in the health and appearance of your Cichlids. It's another one of those trade-offs I alluded to earlier. If you don't believe me, just look at the pallid, washed-out, desperate look of the fish in that tank you haven't cleaned in eons. Once O. lithobates fry reach an inch or so, they can be safely transferred to a larger tank featuring superior filtration and current. This is where the grow-out process begins. The infinitesimal O. lithobates "Yellow Blaze" must fend for themselves, albeit in a predator-free environment. Since they are docile fish, O. lithobates will doubtless make a fine tank mates for all but the most fastidious of African Cichlids. Speaking of which, would anyone happen to know where I might get my hands on a Baenschi female or two? Long live the Lithophiles of Lake Malawi!
Left; This 25 watt Rio powerhead keeps them swimming, Right; These 10 gallon sweater containers make great fry tanks! Photos by Scott Schwerdtfeger.
© Copyright 2002 Scott Schwerdtfeger, all rights reserved
Schwerdtfeger, Scott. (décembre 03, 2002). "Otopharynx lithobates (Oliver, 1989): Lithophiles from Lake Malawi". The Cichlid Room Companion. Consulté le mai 22, 2013, de: http://www.cichlidae.com/article.php?id=247&lang=fr.