Article © Marina Parha and George J. Reclos , uploaded November 23, 2008.
Introduction
Pseudacanthicus leopardus has long being proclaimed a heart winner of a fish. Aquarists are well taken with the fish's stunning looks though word has it that it is rather aggressive and extremely territorial from a very young age. We were both intrigued and fascinated by this fish and ended up with two colonies, one in Manchester, England and one in Athens, Greece. Our colonies grew up in different environments. We took this to be an advantage in terms of understanding the fish and learning about it, so we kept comparing notes all the way. The spawning account that follows has benefited from this approach.
Both colonies were acquired in two stages. In both cases Pseudacanthicus leopardus (L114) were acquired at a very young age and were joined some time later by Pseudacanthicus leopardus currently appearing as L600. The fish were placed in large tanks (1200 and 1300 litres respectively) to grow up. Some of the tankmates of the Manchester colony were, at the time, considerably bigger and quite aggressive (L025s, Acanthicus adonis, L160s etc). Others were of similar size albeit not temperament. In Athens, the tank mates differed: a colony of Paretroplus damii, some Paretroplus small spot East Coast, and lots of different fish belonging to the genus Synodontis.
The fish, as far as we could observe, were quite peaceful and did not get involved in territorial or other fights. During the growing up period they were mostly hiding, probably due to their young age. Most young catfish hide; these youngsters make hiding into a fine art - to the point one wonders if they are still alive.
After about a year in the tank, the L114 still preferred to hide during day time while the L600 became way more visible and started interacting with other fish in the open. We have heard comments to the effect that the L600 type will lose the full orange tail band as they grow up but this didn't happen to any of our fish. The fish kept and still have to-date, the same markings they had when they were purchased.
It's worth noting that in addition to the differences in the markings of the tail there are some further differences in the appearance of the fish. The individuals classified as L114 have more "refined" looks and either grow more slowly than the L600s or have a smaller TL size. The individuals classified as L600 are on the main a broader, much more robust fish by comparison, and they bear a striking resemblance to Pseudacanthicus spinosus (L160) in all but the colour.
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We did debate for a while whether we should keep the colonies mixed or we should separate the fish to L114 and L600 morph colonies. By that time, however, both colonies were well established, each containing individuals of both sexes of each morph. Hence we decided against splitting according to morphs. (1)
The water parameters in Athens and Manchester differ considerably. All fish (wild caught) were acquired at about the same time and had similar sizes at the time of acquisition, which led us to assume that they were roughly the same age. The difference in water parameters was the only obvious one, and we attributed to it the differences in the growth rates of the fish. The colony kept in neutral, soft, tannin-rich water (Manchester) showed a remarkably higher growth rate reaching a TL of 25-32 cm in about 3 years while the ones kept in moderately hard water (Athens) only reached a size of 17-20 cm over the same period of time.
4. L600 Pair, Male above, female lower to side,
waiting for cave to empty so they can enter
The tank mates of the colonies also differed, once these moved to the locations at which they finally spawned. The colony in Athens shares tank with a prolific colony of Paretroplus damii, a pair of Paratilapia small spot "East Coast", a pair of Parachromis loisellei and a female adult Pimelodus pictus. The colony in Manchester, on the other hand, is housed with other catfish: a male L25, a pair of L95s, a colony of L128s, a colony of L137s and a young pair of Paratilapia sp. "Andapa". It is clear that the Manchester colony is disadvantaged, by comparison, in terms of space and privacy, as they do share the tank with other bottom dwellers.
Set Ups
Some information on the set ups may also be of interest. In Athens, the fish are housed in a glass tank 250 x 65 x 60 cm (975 L, 258 US gallons). The tank is serviced by 2 Eheim Professionel 3 and 1 Eheim classic 2213. Other peripherals include:
- two fluorescent tubes, 150 cm / 54 W each with reflector located at the back of the tank
- a 9000 L/h blower which provides aeration via 6 outlets
- one Schego M2K3 (350 L/h) which adds more air via a single outlet
- a classic Eheim automatic feeder and a double chamber Eheim automatic feeder which provide feeding at regular intervals
- three 250 W glass heaters (Jaeger) and two 300 W Schego titanium heaters which are only turned on during water changes or extremely cold days
The substrate consists of calciferous sand mixed 1:1 with quartz gravel of the same colour (light brown). The tank is decorated with large pieces of all kinds of wood, large stones and four ceramic pots for the catfish to retrieve into. The readings are as follows: pH 7.8-7.9, GH: 9-10, KH: 8, temperature 26°C (winter) up to 29°C in summer. (2) We put no additives in the water nor any attempt is made to soften it. The maintenance regime consists of one water change weekly and cleaning the filters when the flow is visibly reduced. During the water change 50-75% of the water is changed; this is upped to 100% during the hot summer months. Water is removed and added at the same time, over a 2-3 hour period, with pipes located at opposite sides of the tank. The new water is usually 1-2°C cooler than the water in the tank. Hands, cleaning magnets and nets very seldom enter the tank (less than once a month). As a consequence fish feel at ease and the catfish are very often seen in the open.
In Manchester, the fish are housed in a glass tank 200 x 80 x 55 cm (880 Lit., 233 US gallons). The tank is low and wide to allow for more space at the bottom for the catfish. It is serviced by 1 Eheim Professionel 3 and 1 Eheim 2260. Other peripherals include:
- 1 fluorescent tube, 150 cm / 54 W with reflector located at the back of the tank (totally ineffective, given the fact that the water is very dark due to the tannins)
- a "shared" 8000 L/h blower which provides aeration via 4 outlets
- two 350 W glass heaters (Jaeger) which maintain a constant 25°C. In the summer months the temperature is raised to 27°C.
The substrate is neutral coloured quartz sand. The tank is decorated with large pieces of bogwood roots with lots of crevices and various sizes ceramic pots for the catfish. The readings are pH 7 - 7.6, GH: 3.5, KH: 3 (with the addition of sodium bicarbonate), temperature 25°C. During weekly maintenance we add a small amount of discus trace minerals to the water to raise the GH to 3,5 dgh. The maintenance regime consists of one water change weekly, changing 80-90% of the water using constant flow (water is removed and added at the same time over a period of 2 hours; during the change the temperature of the tank remains steady). The filters are cleaned every 4 weeks alternatively as they do tend to clog with small pieces of wood and wood dust. There is no netting in this tank except in an emergency (it has happened once in the last 20 months) though the Paratilapia sp. Andapa do get hand fed once or twice weekly and vegetables are provided for the fish three times weekly, which involves immersing hands to secure them on clips. The fish are very settled and they are constantly in the open to the point of "lining up" at the front of the tank when food is being delayed.
Feeding
The feeding regime is similar for both colonies. We feed the fish a variety of foods, all mixed, on a daily basis. Staple food includes a mixture of Dr. Bassleer XXL, Ocean Nutrition Formula 2 - medium sized pellets, OSI shrimp pellets, Hikari Carnivore Pellets and Blue Line Grade 122 Basic. The fish can also eat, should they want to, Ocean Nutrition Formula 1 and Blue Line Bottom Spiru tablets. Ocean Nutrition frozen Bloodworms are also offered once a week supplemented by the occasional treat of frozen prawn or mussel. In addition to the above, the fish in Manchester enjoy fresh vegetables and fruit daily. We have been told that, in the wild, the fishermen catch these fish by putting small coconut trees in the water; the fish collect round their roots to graze, which is an indication that they do enjoy vegetable matter and rasping on wood. In Athens the fish are fed 3 times daily (16:00 main meal, 19:00 2 small quantities, 22:00 2 small quantities; one additional feeding a month prior to spawning). In Manchester the fish are fed once daily, between 18:00 and 19:00.
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Due to our personal circumstances we have not been trying to get the fish to spawn. The colony in Athens is soon to relocate to Manchester, while the colony in Manchester is waiting to go to a dedicated tank. Hence, neither tank had spawning caves. Plenty of wood, rocks and clay tunnels were provided for both colonies to rest in but none of these was suitable for spawning. Furthermore, there was no "conditioning" of any kind; the water parameters were kept stable during the weekly water maintenance.
Other factors
Both colonies grew up in various size tanks and have been moved to their current location prior to spawning. The colony in Athens has been moved a year before spawning while the colony in Manchester has been moved about 8 months before. On both occasions the fish had more space available to them after the move.
8. Gravid female L600
Courting & Spawning
In mid-July 2007 we observed two females in Athens being heavily gravid. One of them was the L114 morph while the other was the L600 morph. Concerned mainly to ensure that nothing would happen to the fish - they did look ready to burst - but also out of curiosity, we decided to provide a "spawning site" should they wish to use it. This was done by adding a large, conical ceramic flower pot, the kind which is used to hang on walls (with one side flat). The "cave" was added in the tank on August 2, 2007 and the nearby decoration (bogwood and stones) were changed round in a way that would keep all cichlids at a distance. The ceramic pot measured 19 cm in length, 16 cm in the opening and about 2 cm at the top (inner dimensions). The entrance faced, sideways, the
front of the tank and was quite close to it. This meant that the current (returning water) would pass by the left hand side of the cave, almost without affecting the entrance.
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Once the "cave" was introduced in the tank, both females rushed to it. The L114, who is the smallest of the two, was the first to inhabit it. Following a period of extensive hostilities between the two females, which resulted in lots of torn fins, the L600 managed to get the pot for herself. The L114, though never seriously disputed the right of the L600 female to keep the cave for breeding since, kept herself close by and did try to occupy it during the times the spawning pair moved out between spawns.
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Having secured a spawning site, the L600 female started courting with the larger L114 male. She regularly visited him in his clay tunnel at the far end of the tank and kept sitting on him or teasing him to entice him to follow her. Eventually, she got him right where she wanted him: in the new spawning location!
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In the following 3 weeks the female would occupy the cave while the male spent most of his time in his own cave at the other side of the tank (approximately 120 cm away from the spawning site) only occasionally visiting the site, in which case the female would stay close to the entrance. For the rest of the time, the female would stay in the cave. During these weeks (August 4-24, 2007), the two fish spent an increasing amount of time together, while most of the time they would share the cave; in these cases the male was always on top of the female. AIl we could see protruding from the cave was either one, or two tails.
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It should be noted that during this period the L114 gravid female was also striving hard to win the male's affections. It was all in vain; the male would chase her away ferociously when she approached him either at his cave or near the spawning site. In fact, he would only allow the L600 gravid female to come anywhere near him; all other Pseudacanthicus were chased away.
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It's well worth making some observations regarding the interaction of the L114 female with the L114 male. Although it is likely fish don't have the kind of feelings humans do, seeing these two interact was a sight that made us feel really sad. She would stay there, next to his tunnel, day and night, gently trying to get his attention. The male would respond by moving his tail frantically which was interpreted as a rejection. It should be noted that all the L114 / L600 individuals were quite nervous during that time.
We were witnessing a male of one morph showing an obvious preference to a female of a different morph when a gravid female belonging to same morph as him was both available and "willing". The preference indicated was crystal clear: the L114 male would attack the L114 female every time she came close to him while the L600 female was playfully accepted and followed around in the tank. So much so that to-date, having spawned with her a number of times already, the male only allows this particular L600 female to stay close to him, whether she is gravid or not. The significance of this preference is accentuated by the fact that the two L114s have grown up together (they lived in the same tank for 4 years), while the L600 individuals, who were kept in a different tank by themselves, were introduced to this tank only a year prior to spawning.
On the 24th of August in the afternoon the tank had its usual water change. This resulted in a drop of temperature of about 2 degrees. A couple of hours later the pair, who were in the meantime in and out of their cave, disappeared inside it. Slowly after we noticed the male's tail going in and out very fast, which indicated the male was performing a pumping move facing inwards. About 20 minutes later the male disappeared totally in the cave. Though we recognised at the time that this movement was way different and much more rigorous than anything we had observed in the past we paid no particular attention. As a consequence, we failed to see the female leave the cave. Instead, the next thing we noticed (around 9 pm) was the egg ball laying on the substrate while a very frustrated father was facing it. Regrettably, it looked like the large opening of the clay pot had its drawbacks. Although it made it easier for the pair to casually lay in there together and familiarise themselves with the spawning site, the male couldn't keep the eggs in it. The egg ball was thrown out of the cave either as the female was leaving or while the father was repositioning himself to guard it.
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We considered placing the eggs back in the cave and allowing him to go on with his parental duties. Experience has shown us that some fathers will continue to take care of the eggs after such an accident, others will not (they will eat the eggs). At the time we didn't know what kind of father this particular male (called Mr Superior) was, as this was his first spawn. Future spawns made it clear that he is absolutely exemplary; on one occasion he has laid down his own life to prevent harm to his youngsters. At the time we didn't know that, of course, so we removed the eggs immediately (much to the very obvious distress of the father) and placed them in a separate 10 L tank with Methylene blue to keep fungus at bay. The male stayed by the spawning site for a while, then returned to his own cave. For the rest of the night and the following day he kept visiting the spawning site, clearly distressed. A couple of days later he permanently moved to his own cave, with the female occasionally visiting and resting nearby.
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We immediately replaced the pot as it was clearly unsuitable as a spawning site. We chose a ceramic pot which has a narrow opening but becomes much wider in the middle. This allows the pair to spawn in the wide end while makes guarding the entrance much easier for the male. As the pot is laid along its length, the lip of the opening forms a "step" which prevents the eggs from being accidentally thrown out. The new pot was placed exactly at the spot the previous pot was and we left nature take its course, hoping for the best. Indeed, shortly after, our female was checking out the new "cave".
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Subsequent spawns in Athens followed the same pattern in terms of courting. The L600 female is the one which will orchestrate everything; she will first lie close to the male, making her presence as obvious as possible. When she is sure she has attracted his attention (which means him spending more time out of his cave - close to her) she will search for a cave to spawn. At this point any rival female, gravid or not, will have to give way to her. Otherwise serious fights will go on until the 'rival' female leaves the cave to her.
When the L114 / L600s decide to fight they are dead serious about it. After the female secures the cave, she will go close to her male again and somehow make her victory known to him. We don't know what kind of chemicals (hormones or other) are released in the water at that time but there is some sort of communication between the members of this species (in this case, the two gravid females and the male). For instance, although the L600 female left the cave empty to visit the male's territory, the L114 gravid female did not attempt to re-occupy the spawning site.
Following those calls, the male will start to visit the cave every day for some time checking both the place and the female. When the female is ready to lay eggs she will enter the cave and the male will come in after her, blocking the entrance with his body. The pair may stay in this position for as many as 4 days (10 days the first time they spawned, 3 days the second time, varied in subsequent spawns). After that, the female will exit the cave and the male will stay there fanning and guarding the eggs.
The second time this pair spawned spawning was quicker. Both parents knew exactly what to do and didn't waste time as in the previous spawning which lasted almost a month, courting included. This time, it took them less than a week. We observed that the male decided how many eggs he could guard and fan efficiently, which we presume depends on the space available in the cave. When enough eggs were laid and fertilized, the male pushed the female out of the cave and blocked the entrance. The - still gravid and laying - female made a couple of attempts to re-enter the cave (even climbing on the male's body in an effort to pass through the narrow opening) and lay more eggs however the male did not allow her to and, when she became too persisting, he actively chased her away.
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We have observed this behaviour on other occasions too, mainly when our L144 spawn. In more than one instance the female coming out of the cave was still gravid (although visibly less than when she entered the cave) while in one case the L144 male decided to get rid of the excess eggs by throwing them out of the cave while keeping the majority in it, giving them excellent parental care. The eggs thrown out of the cave were fertilized, so we ended up placing them in a different tank and letting the fry hatch in there.
In Manchester, things took a different turn. Two pairs formed almost at the same time. The first pair consisted of the second largest L600 male who "chose" an L114 female. The second pair, which we observed about a month later, was 2 L600s. On both occasions courting was initiated by the male who would wait for the female in the open space of the tank after feeding times. She would then descend from the woods and they would interlock and play for as much as 30 mins at a time. Following this the male would retreat to his cave while she would join the other females under the wood.
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Naturally, the male of the first pair (L600 x L114) didn't consider his own "cave" suitable for spawning either (he occupies a clay tunnel open at both sides). A week after courting was initiated, he started looking around for a spawning site. He identified a clay pot in the middle of the tank, which was intended for the L128s and got himself in it.
We observed him for 2 days going around in the pot. We secured the pot firmly, but the fish was still seen in the middle of the tank rolling in the pot. It became apparent he got stuck in it, so we broke the pot and freed him. Thankfully he was alive with no more than some pretty nasty scratches on both sides. The fish disappeared in his own cave and courting got temporarily suspended.
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We added a much larger round clay pot (30 cm length x 9 cm width x 9 cm height at the opening) at the far end of the tank facing the water flow. Water flows pretty fast in this tank; the turnover is roughly about 4 times per hour. The pot was secured with slate and wood, and the entrance got partly covered with wood.
Courting resumed a couple of weeks later, but the new "cave" remained uninhabited for about a month. The male did identify the new site but he was clearly "weary" of it. He spent hours close to the entrance; while the female was sitting on top of the cave observing him, he was dashing in and out of it very quickly. The fact that our female Paratilapia sp. Andapa used this cave as a hiding place to avoid her male didn't make things any easier.
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A week prior to spawning the courting became very long and intense. The sides of the female had grown to monumental proportions. Water temperature was steady at 25°C; the feeding regime remained the same. The only particularity with this tank is that it gets really big water changes very often, as the dissolving wood particles clog the filters and colour the water almost black (you can see that from the "quality" of the photos, or lack of it...). The male ventured in the cave and stayed there for half an hour initially, followed, in subsequent days, by longer periods. During this time the female would always rest on top of the cave. Courting activity ceased. Two days before spawning the female got in the cave and stayed there for 48 hours (at least we didn't see her coming out at all. For all we could see she stayed in the whole period.). When she emerged, the proud father was fanning eggs.
Eggs & Fry Development
The egg ball measured 2.5cm x 6.5cm approximately and it contained 120-150 eggs. The "white spot" on the eggs indicated they were fertilised. (3)
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We placed the eggs in a 10 lit container with an air filter, an air stone set on low and located in the opposite side of the container so as not to disturb the eggs and a thermostat keeping the water at the same temperature as the one of the tank in which they were laid. We followed a routine of repeated baths in methylene blue (2 mg/L) with 100% water changes (using constant flow) every 12 hours over a period of 3 days. Methylene blue was then totally removed. On the fifth day the egg ball was still together; there were only four infertile eggs while the first fry emerged.
We moved the newly hatched fry and the egg ball from the hatching tank to a grow out 100 lit tank. The tank was furnished with wood and stones and was supported by two filters, an Eheim classic 2213 and an Eheim hang-on filter. Strong aeration was provided by two air stones connected to a shared blower. To do so, we slowly scooped up the egg ball using a large, clean tea cup, which we then lowered carefully in the water of the new tank, thus releasing the eggs. The remaining of the eggs hatched hours later. The fry scattered on the substrate, wood and stones and didn't seem at all distressed by the absence of their father or a cave.
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Photos of the second day post hatching show clearly the dentition of the fish. We were impressed by the shape of their pectoral fins, which, in variance to these of other L-numbers, have a heart shape. At this stage the fry split into small "colonies" living at different parts of the tank. Fry activity clearly increased while the fry were able to attach themselves on the glass and other surfaces for short intervals.
As the fry were hiding most of the time, it was difficult to observe precisely when the yolk sack was consumed by each and every one of them. On day 8 we started providing home made fry food in case we had any fast developers. This consisted of a mixture of foods, as described below. On day 9 all the fry had consumed their yolk sack, while on day 12 they could be seen out foraging. At this stage the fry were black with white spots and tail. It would be rather difficult to associate this colouration with the one of the adult fish. (4)
39. Feeding mixture
The fry in Athens were fed 6 times daily (midnight, 3:30 am, 5:30 am, 8 am (lights off), 4 pm and 10 pm (lights on). The feeding mixture for the first 10-12 days consisted of Jade 100% spirulina powder (Salt Creek Inc., USA), Cyclop Eeze (Argent Laboratories, USA), Ocean Nutrition formula 1 and 2, OSI shrimp pellets, Tetra discus (all of them powdered in a blender), and Paragon fish feeds 1 (Salt Creek Inc., USA. On the 10th day this was replaced by Baby Star 2 (Inter Ryba GmbH) (5). The powders and the paste were mixed with a vitamin solution (Multivit by Wiegandt GmbH) till we got a low viscosity, nearly homogenous pulp which was then transferred with a plastic syringe to the fertilizer compartment of an Eheim Liquidoser. From the 10th day onwards we added an extra feeding session. To compensate for the immense amount of food in the tank, we performed really big water changes daily (about 75%). (6)
The fry in Manchester had two different routines. The ones left in the main tank were fed once daily, while the ones removed for observation were fed twice daily (9 am and 6 pm, lights on) with 100% pure Spirulina powder (followed by Blue Line Spiru grains), BlueLine Artemia grade12 (followed by Blue Line Artemia grade 35), Blue Line Basic grade58, Ocean Nutrition 1 small, and Dr Basleer medium, ground. Esha minerals and vitamins was added to their water. It is worth noting that the Manchester fry were placed in a 20 lit planted tank supported by an air filter to grow up. They shared the tank with 5 L046 fry and 5 female Betta splendens. There has never been an incident between the fish till eventually the pseudacanths were moved out to a larger tank.
Increased activity during feeding times, rather than constant observation of the majority of the individuals, convinced us that the fry were eating well and growing well. A comparison of growth and survival rates indicated that both fry colonies had the same growth rate. Survival rates were excellent, over 98% in both cases. (7)
From about day 12 onwards the fry became a bit more adventurous and started coming out of their hiding places to forage. On day 18 they had developed yellow spots on their body, though the tail still remained translucent. We noticed that some fry started developing a melanin pattern on the tail. This was quite interesting as we knew their parents had different tail patterns (one being the L600 morph while the other being the L114 morph).
On day 15 we started offering different size pieces of food; some was totally ground (for slow developers) while other particles were bigger. Uneven growth rates are common in fish; if the food offered is covering the needs of one section of the fry population, the other sections will starve, sometimes to death. This is one of the most common reasons for losses during this stage. Larger fish can't feed on tiny particles. Even if they do they will consume much larger quantities (essentially by keeping a large part of the substrate to themselves) while they are able to keep their smaller sized siblings away from food, thus driving them to death by starvation. On the other hand, small fry can't feed on large particles; by the time they locate a piece and start rasping on it a bigger sibling will come along and chase them away from the food. In short, one needs to make sure that particles with sizes ranging between acceptable limits are always present at the tank, at least till the fish reach the age of 1-2 months (depending on the species and the way of feeding).
At this stage we also tried varying the feeding strategies to observe the outcomes. Fry can't consume massive quantities in one go. One theory was that they grow much better on smaller, more frequent feeding sessions. Feeding sessions in Athens were increased to eight per day. Four of them were 'automated' (using the Eheim Liquidoser); at 7 am (no lights), 1 pm, 8 pm (lights on) and finally 2 am (lights off). Each session consisted of approximately 5 ml of the pulp mixture. Four more feeding sessions were done manually, at 4 pm (small pellets), 6 pm (pulp mixture; 5 ml), 10 pm (small pellets) and midnight (just before the lights go off, small pellets).
Fry in Manchester, on the other hand, continued with their two feeding sessions daily. Both feeding sessions took place during lights on (9 am and 7 pm). The results showed that there were no significant differences in growth rates, though some of the "Athenians" were definitely the chubbier fry - the sizes of some bellies were absolutely unbelievable! (8)
In terms of pattern (colouration) the development of the fry from the first day post hatching until day 13 was as follows:
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On day 16 the fry had grown considerably but still did not resemble their parents. The photo shows a loner who ran across the front glass of the tank then climbed on it, stayed there for some seconds and finally disappeared. We noticed that some of the fry in Athens seemed underfed. We decided to increase feeding substantially, especially during night hours, when they come out actively looking for food. (9) Starting on day 17, the amount of food added per feeding was virtually doubled (if not tripled). With this amount of food added daily in the tank, the two pre-filters got clogged every other day and needed to be cleaned, but we were determined to raise as many of the fry as possible. (10) The same difference in body fat wasn't observed in Manchester, possibly because the fry were in a considerably smaller tank, making feeding easier in terms of accessing the food.
By day 28 the tail had assumed its orange colouration adorned with black spots in most cases. We had more fry with a melanin pattern in Athens so we assumed that the difference in water may be critical in determining the colouration of the tail. The average TL was 1,5 cm, which compared very favourably with other L number catfish we have bred.
The fry remained well hidden during the day but were very active at night and video (day23). We could only see a fraction of them and were wondering how many were surviving. Survival rate on every occasion proved to be excellent. We counted over 150 fry reaching the 5 months mark while we retrieved less than 5 casualties in every spawn.
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Day 30 was important to us - and the fry. Experience has shown that if any mass casualties are to occur, they will usually occur by this stage. Fry who make it to this date have got excellent chances of survival. On examining the tanks we found the expected uneven growth (with some fry being as much as 50; bigger than some of their siblings). The growth rate was impressive, by comparison to the Hypancistrus species, for example, but still less than expected for a fish whose TL exceeds the 30 cm mark. In the photos below, the difference in body mass of the two youngsters is evident, despite the distortion due to the rounded corner of the fry raising tank.
By day 40 all the fry had spots on their tails. They were feeding well and gained substantial weight. That was the time the Manchester fry were moved out to a 60 lit tank. They had grown considerably and were mostly out in the open, rather annoyed, as their panting indicated. We believe this was due to a combination of not enough hiding places and low oxygen supply, as the tank was serviced by an air filter, which was clearly unsuitable as the fish were growing. Once in a larger tank, with a notably faster flow, they all went hiding again and their breeding returned to normal.
51. "Mr Superior" with wounds and fungus.
He was attacked by the L600 male challenging him for his cave.
Despite our expectations and assumptions the tail pattern reversed. By day 60 all the fry had lost the melanin pattern of their tails and they assumed the full orange tail colouration. That was a surprise!
By the end of their fourth month the fry were measuring an average of 5 cm TL. Clear differences of the shape of the head, which is one of the ways to sex the fish, were visible when looked from above.
All pairs spawned again 2-3 months later and continued, to-date, spawning at the same interval, always with the same partner. During the third spawn an interesting, though thoroughly distressing, incident, took place in Athens. The L114 female who was rejected by the L114 spawning male started courting with an L600 male. We noticed the pair making advances towards the cave of our established pair there, so we provided a second spawning site. Despite that, the L600 male savagely attacked the L114 male while he was guarding his eggs in an attempt to gain control of his spawning site. The L600 was unable to get inside the cave so he started literally chewing the back end of the body of the L114, which is all he could reach. To his credit, the father remained guarding his eggs despite what must have been an excruciating pain. We removed the L114 in pretty poor condition and treated him with TAP Aquagel. The fish recovered fully in a couple of weeks and has subsequently resumed his spawning activity. In Manchester, the second pair has not, to-date, exhibited such a behaviour. They use the same cave as the first pair when it is available (the male of the first pair leaves the cave when all the fry are out and returns to his tunnel, while his partner goes with him to the tunnel and rests above it or nearby).
End Notes
- There is some disagreement concerning the identification of Pseudacanthicus leopardus and the L numbers corresponding to this fish. For the accuracy of this account we will refer to the two morphs with their current L-number classification. L114s are the individuals with a spotted pattern which extends to the end of the tail; they are smaller and more slender by comparison to the fish classified as L600. L600 have a tail with a solid orange band, are bigger and much sturdier, resembling more in body to L160. We refer to both morphs as Pseudacanthicus leopardus as there is also disagreement with reference to the name Pseucacanthicus leopardus and Pseudacanthicus cf. leopardus. It should be noted that our L600 variant has a much darker base colouration when compared to the L114. See Ingo Seidel, Back to Nature, Guide to L-Catfishes, Fohrman Aquaristik AB, Sweden, 2008, p. 173.
- Subsequent spawns by the same pair in the same tank took place in different water parameters: Temp 30°C, pH: 8.2, GH 12 (400 µS), KH: 18, salinity: 1.3 µS, NH3: none, NO2: none, NO3:15 ppm.
- The photos used in this presentation have been taken during 5 different spawns. Photos of the egg ball and hatching were taken during the only time the father accidentally kicked the eggs out of the cave. In other spawns this didn't happen and the eggs and fry were left with the fathers to be taken care of. About 30 fry in Manchester were collected when they were about 10 days old and were brought up in a separate tank for observation and comparison with the broods in Athens. The photos showing the melanin pattern of the fry (days 1-13) are showing fry of the same brood over a 13 day period.
- The fry spend all their time hiding under wood or stones, therefore keeping a regular and consistent photo diary is an almost impossible task if one doesn't want to disturb them way too often. Things would be much easier in a bare bottom tank or hatching nest but we have had previous experience with fry which didn't do well under those conditions. There is evidence to prove that fry grow much better in fully aquascaped tanks (e.g. see Spawning Paretroplus damii) so we preferred that environment to taking the risk of losing them. The drawback is that you know a lot less about what actually goes on in the tank. The advantage is that with some species you get a higher survival rate, with others a much healthier bunch of fry, and in every case the juveniles can be transferred to any tank without serious acclimatization issues. We have had really bad experiences when we tried to transfer fry which stayed too long in a floating nest or bare bottom tanks in fully aquascaped tanks, especially when competing populations were present. The youngsters simply didn't manage to survive in the new environment - either they were unable to understand what they had to do in order to survive or they were phased by the new environment.
- It is a real pity that Paragon fish feeds 1 is discontinued since it has worked well for us over the years with various fry, however we managed to get as much as possible of this paste from various sources.
- It has been reported that catfish fry generally dislike large water changes during the early stages of their life but no filters would be able to cope with the particular feeding scheme. That apart, we have not been able to confirm this report while raising fry of any species we have bred, cichlid or catfish. We suspect the difference could be due to the way we perform water changes which differs from the "usual" way most hobbyists do it, i.e. remove a large part of old water and then replace it with fresh water. We prefer to make long water changes during which old water is slowly removed from the tank while new water is added. This results in a far more gradual change of the water parameters which seems to be better tolerated by the fry (and the adults).
- The fry left in the parents' tank in Manchester were growing slightly more than the ones which were removed for observation. This was expected. Naturally, we cannot report on the survival rates of this colony of fry, which, however, we expect to be much lower than the ones we raised artificially. This is usually the case.
- Water parameters, checked immediately after a water change (day 13) were as follows:
Athens: Temperature: 30°C, pH: 7.5, GH 7, KH: 10, NH3: 0, NO2: 0, NO3: 0. It seems that the presence of a huge amount of bogwood in the tank made the water a bit softer. The same parameters, immediately before the next change (day 14) were as follows: 30.3°C, pH: 7.5, GH:7, KH:8, NH3: 0, NO2: 0, NO3: 0 (a bit surprised here, we were expecting them to be in the 25 - 50 ppm range). It is evident that you can change as much water as you want and the fry will not even notice it.
Manchester: Temperature: 28°C, pH: 7.6, GH 3, KH: 3, NH3: 0, NO2: 0, NO3: 0. - With regards to food availability it has been reported that there is experimental evidence to support the view that bigger amounts of food offered to young fish reduce the death rate amongst them but do not influence their growth rate. This makes sense; provided the amount of food offered in the first instance is adequate (i.e. the fish don't suffer from deprivation) the growth rate is genetically dictated. The additional amount of food will be consumed by weaker siblings who would otherwise die from starvation due to not been competitive enough to fight over limited amounts of food.
- You simply can't believe how active these little guys become at night. They are virtually all over the place and you can frequently see someone swimming across the tank.
- Special care should be taken when removing anything from the tank to clean it, since the fry may regard that particular part as a good hiding place. This is especially valid for internal filters or pre-filters - fry gather round them to eat the food that gets accumulated there.
- A report of this spawning was published in Amazonas Magazine 18, July - August 2008, pp. 34-42.
There is further information on this species on the Cat-eLog page.
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