Cichlid Fish Forum banner
1 - 1 of 1 Posts

3,932 Posts
Discussion Starter · #1 · (Edited)
Keeping & Breeding Satanoperca daemon
(Heckel 1840)
by Lee Newman


Nature Organism Fin Fish Adaptation

Satanoperca daemon

Over the last fourteen years I've had occasion to keep S. daemon on three separate occasions. The first time, I had maintained six fish for about three years during which they spawned a number of times, unfortunately to no avail. I suspect inappropriate water chemistry parameters were likely at fault. While the tap water was very soft and slightly acidic in pH, I made little effort to simulate blackwater conditions. Unfortunately all six fish eventually succumbed to Neotropical Bloat when water quality was permitted to decline during a fishroom re-construction effort. For the second time, I was living in an apartment. Again, I acquired six fish and despite the best of care, they failed to thrive. I finally found the cause to be an excessive amount of copper in the tap water. Apparently, some of the hot water pipes in the apartment building had been changed and were leaching free copper ions because of the soft, acidic tap water. Most recently, I acquired seven individuals and earnestly applied all that the two previous experiences had taught me. I also employed the knowledge gained in my more recent successful experience with S. acuticeps - with affirming results.

Water, Chemistry and Quality

Satanoperca daemon is found in blackwater environments in Colombia and Venezuela characterized by pH values between 3.5 and 5.3, barely any detectable hardness and very low conductivity. Because of the relatively extreme hydro-chemistry in the wild, my efforts to successfully breed S. daemon in the aquarium inevitably involved some water chemistry manipulation.

For the time being, at least until the local water authority fully makes good on their promise to protect their expensive distribution pipes by increasing the pH and alkalinity, Vancouver's tap water is extremely soft and just above neutral in pH. For those of us keeping blackwater fishes it also has, for the time being, the added benefit of being very poor in alkalinity.

The only evident and critical drawback to the otherwise suitable tap water was its aforementioned effect on domestic copper piping systems. Soon after moving to a house, in an effort to mitigate the effect, I constructed a relatively simple water treatment and storage system. Effectively, tap water is directed through two vertical packed columns of Cupri-Sorb , a metal chelating media made by Seachem, then collected in four, 55-gallon food-grade plastic barrels that are aerated and heated. The four plastic barrels were plumbed together with a water pump included for distributing the treated water to the appropriate aquarium during a water change.

Given the chemistry of the tap water I did not feel it necessary to go to the expense of a de-ionization or reverse osmosis system in order to effect the water chemistry parameter changes I needed. Rather, I elected to use the low-tech approach to produce appropriately simulated blackwater: peat moss. The use of peat moss in such applications is well documented in the hobby literature. According to Gargas (1998), peat moss lowers water hardness, decreases conductivity and lowers pH primarily by exchanging Hydrogen ions (H+) for other cations such as calcium and magnesium. I simply placed a filter bag full of un-boiled peat moss in the flow from the aquarium's powerfilter. Together with some additions of "peat tea" - boiled peat water - it took only a few days for the pH to drop into the range of 4.5 - 5.0. While I suspect that the peat in the filter bag may have also had an effect on the water hardness, I made no attempts to measure it, as the tap water was already very soft (

Inevitable or Preventable?

Aquarium-held S. daemon have been affectionately described as "little time bombs" that will eventually "bloat up and die" for no apparent reason, obviously in reference to a notable susceptibility to Neotropical Bloat. The most widely held opinion as to the cause is degraded water quality and most efforts at effecting a cure are directed at identifying the guilty pathogen and selecting the appropriate chemotherapy. However, in many cases the chemotherapy proves to be of limited value, although some success using Naladixic acid or Metronidizole has been reported, simply because a liable pathogen can not be found. Precious little work has been done with Neotropical Bloat and the exact cause is probably hidden in the numerous physiological responses to environmental stress.

Satanoperca daemon is also very susceptible to neuromast pitting. Referred to some, as "hold in the head," it is actually a very different condition. Whereas classic "hole in the head" appears as tiny volcanoes erupting from holes in the affected fish's head, neuromast pitting appears to be a necrosis, or death, of the epithelial tissue around the sensory pores (neuromasts) in the head. It starts as tiny pin-sized holes and left unchecked, gradually worsens, certainly disfiguring, and sometimes eventually killing the affected fish. It appears to be very similar to the "disease" that affects many species of marine fishes, Head and Lateral Line Erosion, or HLLE.

In the hobby literature there have been a couple of recent articles discussing the identification, description, causes and treatment of HLLE (Hemdal 2003, Bartelme 2003). While most of their work involves marine species, much of what they had to say applies equally well to freshwater fishes. In particular, Bartelme hypothesizes that HLLE in marine fishes is actually an autoimmune disease, a malfunctioning immune system, precipitated by long-term stress. I suspect, along with a growing number of others, that neuromast pitting in S. daemon (actually, all freshwater fishes so affected) is likely the same thing, a physiological response to environmental stress. Degraded water quality is perhaps just the most common form of environmental stress for S. daemon in a captive situation. Unfortunately, the prognosis for full recovery is highly variable. First one has to be able to find the cause, or causes, of the stress and then take the necessary steps to relieve it. Then be able to determine what steps can be taken to correct the function of the immune system.

Quite a while ago I learned how to reliably keep S. daemon from pitting. Use the largest aquarium you possibly can, keep the pH, hardness and conductivity low, keep waste product accumulation low as well by performing large frequent water changes, feed an appropriate diet (more about that to follow), house them with suitable heterospecifics, if any, and don't crowd them. I should also add, that while one can keep, and grow, S. daemon in water of significantly more modest chemistry, the practice probably leaves the fish more susceptible. I've found that prevention is a far better alternative to a long-term treatment regime for the unsightly erosion caused by neuromast pitting.

Large Fish, Small Food

Regrettably, many of the S. daemon imported for the trade get offered, and are therefore obliged to accept, a captive diet representative of that usually offered to other similarly sized cichlid species. It often bears little resemblance to what might be construed as a more reasonable substitute for what is consumed in the wild and many individuals simply fail to prosper under such treatment.

The diets of wild cichlids (gut content analysis) are rarely reported in the hobby literature. The idea, of course, is to use the gut content analysis of wild-caught fish to model a diet suitable for the representatives in captivity. Luckily, in some cases, the information is available; you just might have to search a little. I had done that research in my effort to successfully keep S. acuticeps, finding comments on the feeding behavior of several Satanoperca species in the scientific description of S. lilith (Kullander and Ferreira, 1988). While S. daemon was not among those listed, it seemed reasonable to assume, given the morphological and meristic similarities between S. daemon and S. lilith, that the two might share trophic similarities as well.

Included in Kullander and Ferreira's 1988 description of S. lilith was a section on gut content analysis. They reported that the primary food items during the flood season were Cladocera ("water fleas"), Ostracoda (seed shrimp) and Conchostraca (clam shrimp), the largest of which measured no longer than about 10 mm (1/2 an inch), and the aquatic larvae of Diptera (true flies), Coleoptera (beetles) and Trichoptera (caddisflies). The items taken in the dry season were predominantly insects and plant matter. The take home message is not that one need attempt to culture large, reliable quantities of seed shrimp, but rather, despite the relatively large adult size of S. lilith, it feeds on surprisingly small food items. In the wild, S. lilith and S. daemon reach comparable adult sizes - about 12 inches SL.

In the aquarium, the wild diet of S. lilith seemed easy enough to model; frozen bloodworms fit the bill for insect larvae and frozen brine shrimp seemed like a good way to get a crustacean component into the diet. A home-made gel diet, taken from Enjoying Cichlids (Konings 1993) and used successfully on S. acuticeps (Newman 2001) entered into the equation because it was composed of very small particles and combined an additional crustacean component as well as a plant matter component. As expected, the new group of seven S. daemon greedily accepted the gel diet.

More recently, I've been in contact with a researcher at Texas A&M University who has spent time in the field studying the feeding behavior, and diet, of wild S. daemon. In personal correspondence, he described how in approximately 300 fish ranging in size from very small juveniles to full-grown adults the most significant food item was Chironomid larvae - bloodworms. He therefore suggested that bloodworms make up a significant portion of the diet of captive S. daemon. Evidently, the gut content research explains the enthusiasm S. daemon show toward bloodworms despite the list of objectionable qualities cichlid keepers often report with them.

Satanoperca daemon in the Aquarium

Organism Fin Fish Adaptation Marine biology

Satanoperca daemon

I acquired the group of seven fish in October 2001. At the time, they were all about 2 - 2.5 inches TL and in relatively good condition. I placed them in a 90-gallon species aquarium aquascaped with a fine sand substrate and some water-logged wood pieces. The aquarium was filtered with two high-volume, air-driven box filters packed with a small amount of pH buffer media (crushed coral gravel) and floss and was only weakly illuminated. The pH varied slightly between 5.5 and 6.0, KH was less than 5ppm (CaCO3) and temperature was maintained between 82 F and 86 F. Within hours of their introduction the seven fish eagerly accepted frozen bloodworms.

Despite being housed on their own, the fish were not shy or reclusive at all. In fact, they very quickly learned to associate my approach to the aquarium with the offering of food and often jostled for position at the surface in anticipation of the meal.

Over the following months, with regular filter cleanings and 80% bi-weekly water changes, the fish grew well. In August 2002, I moved them into a 180-gallon aquarium. There was remarkably little variation in size between the seven fish; all were about 4.5-5 inches TL. The larger aquarium was aquascaped with fine, white silca sand with two small pieces of water-logged wood and filtered with an AquaClear 500, loaded with two foam inserts, and two air-driven corner box filters packed with only a small amount of pH buffer (crushed coral gravel) and filter floss. A single 20-watt, cool-white fluorescent bulb provided low-level illumination for about 12 hours a day. Large partial water changes (70-80%) and filter cleanings were carried out about every 2 weeks. Water chemistry parameters were very similar to those of the previous, smaller aquarium.

By April 2003 the seven fish had grown to approximately 8-9 inches TL. They had also become clearly sexable. The males were slightly, but very noticeably, larger than the females, which were clearly evident by a much fuller looking abdomen profile. It appeared as though I had four males and three females. One morning in late April, something spooked the fish causing them to dash wildly around the aquarium and crash into the glass walls of the aquarium. Unfortunately, one of the males did not recover from the ordeal. While I was disappointed I had lost one of the fish it did leave me with three males and three females - arguably a great sex ratio given my intention of eliciting a successful spawning.

Modified Substrate Brooders

Water Photograph Fin Organism Fish

Satanoperca daemon

In early May, I noticed that two fish, one longer and more slim than the other, were spending a significant amount of time together near the substratum. Over the ensuing few days they began to excavate a pit and direct some aggression towards the other four fish - often relegating them to the upper layers of the 24-inch water column. By May 10th, the entire bottom of the 180-gallon aquarium had been excavated with the bottom glass exposed in most areas and huge piles of sand pushed up against the front glass. It also appeared as though they were trying to bury one of the box filters! On May 11th, I got home from work just in time to watch the female deposit eggs among several rocks in the excavated pit at one end of the aquarium. Remarkably, the eggs were being extruded in a fashion very similar to salmon (Oncorhynchus spp.)! Unlike other Satanoperca species (including S. acuticeps) spawned to date where the eggs were placed on the spawning site surface by direct ovipositor contact, the female released a batch of eggs in a continuous extrusion from an inch or two above the spawning site!

Unfortunately, the event was short-lived. The male, rather than defending the female and their spawning site, was busy eating the eggs as fast as they were extruded. The other four fish also created an additional amount of pandemonium in their largely successful efforts to dine on the newly laid eggs. Within a few hours, it looked as though nothing had happened - save the much slimmer female.

Three weeks later, on the 31st, a day before I was to leave for a week on business, the same pair spawned again. While I had prepared the aquarium for any future nuptials by removing the surplus four fish, on the advice of my friend Alf Stalsberg, from Norway, suggesting the pair would need privacy to successfully complete the process of spawning, the ill-fated timing was not of my design! This time the female spawned over a depression in a piece of water-logged wood. While I did not actually observe the spawning, it was clear that the female would not have been able to place the eggs directly because of the size and depth of the depression. Also, some of the eggs were scattered about the piece of wood in a seemingly random fashion and more or less sticking to its surface. The eggs in the depression had also been covered with a collection of small pieces of wood and the male and female were taking turns at fanning the eggs.

The next day I left for my business trip leaving my wife, Lisa, generously recording the details as they unfolded. Lisa observed that the pair had uncovered the eggs after two days and appeared to be moving the larvae to another location in the pit. However, after two more days the pair resumed normal activity and took no further interest in the spawning site, or pit.

Photograph Nature Water Organism Fish

Satanoperca daemon

On June 23rd the pair spawned again in the same depression in the wood piece and I was fortunate enough to observe the process. A few days prior, the female had developed a strong interest in the depression and was frequently observed cleaning it of sand and debris. The pit, still involving the entire floor of the 180-gallon aquarium, also received a bit of attention at that time, mainly from the male as he tried in vain to pile the sand higher up against the front glass.

After a few dry runs, the female was observed extruding eggs over the depression, up to approximately 20-25 at a time. Frequently, water currents from the AquaClear 500 caused some of the eggs to drift away from the depression and land on the wood piece itself. These eggs seemed to be adhesive, but also appeared to be easily dislodged by the action of the adult fish directly over them. Periodically, the male would slowly glide over the depression, presumably fertilizing the eggs.

The actual process of spawning was brief, lasting only about 15-20 minutes, not the often-reported standard of an hour or so. Then, after the female had extruded her eggs, the pair collected small wood pieces (~ 1 inch) from around the aquarium and placed them in the depression on top of the eggs. At this point there were a couple of interesting distinctions to make between S. daemon and S. acuticeps. In this case, the S. daemon were observed to extrude eggs, rather than in S. acuticeps where the eggs were deposited directly on the spawning site. Also, S. daemon concealed its eggs with relatively large material, whereas S. acuticeps concealed its eggs with only a fine layer of sand (despite having small wood pieces abundantly available).

Soon after the adults had covered over the eggs, they started taking turns fanning the site. While the male did participate, it was clear that the female dominated the task. The male was permitted to fan the eggs frequently, but only for very brief periods, up to about 10 seconds or so. They fanned the eggs for two days and on the 3rd day post-spawning the eggs hatched and the pair uncovered the larvae. Unfortunately, the intense fanning of the adults (between 8-9 inches TL) caused some of the larvae to be "swirled" out of the depression, whereas the female would retrieve the youngsters and spit them back into the depression the male simply ate them. Fearing that the male might eat all of the larvae, I intervened.

Organism Adaptation Thigh Font Art

Satanoperca daemon

I had intended to siphon only about half the brood into a large jar, but ended up stealing all the larvae. I could not see very well into the depression and clearly misjudged the siphon's efficiency! The larvae spent 4 days in the jar, which had been covered with a net and submerged in the 180-gallon aquarium in front of the flow from the AquaClear 500 to ensure adequate circulation. The larvae became free-swimming on the 5th day, shortly after having been moved to a 15-gallon aquarium that had been previously set up to float in the 180. Hours after they became free-swimming, they eagerly accepted newly hatched Artemia nauplii for their first meal. Within a few days it was slowly starting to occur to me that I had made a terrible mistake. The almost total euphoria I felt for having finally succeeded in getting fry from S. daemon was over-shadowed by the cruel realization that I'd quickly run out tank space and have to resort to flooding the basement if they all survived. The fry were greedily eating all the Artemia I could hatch and quickly started to crowd themselves in the 15-gallon aquarium, so I moved them to a 34-gallon aquarium, set up with a fine sand substrate and filled with water from the 180-gallon. A simple air-driven box filter packed only with filter floss filtered the new fry tank.

Again, at this point there were a couple more distinctions to make between S. daemon and S. acuticeps. Whereas the newly free-swimming fry of S. acuticeps seemed to have some trouble taking newly hatch brine shrimp for their first meal, the S. daemon fry had no such problem. To them it somehow seemed intuitive that the little red specks jerking about in the water column were food. Also, where the S. acuticeps fry clearly stayed in the water column for several weeks before developing an interest in the substrate. The S. daemon fry, on the other hand, seemed to know right away what their pointed little snouts were supposed to be used for and promptly began sifting at three days post free-swimming.

After a couple weeks in the 34, I moved the S. daemon fry to a 72-gallon aquarium, set up the same way as the 34, but with an additional box filter. Later as they grew, I added an AquaClear 300 to the 72-gallon. By the time they were moved into the 72 I could no longer keep them full of newly hatched Artemia nauplii, and so began the process of weaning them on to more convenient foods that I could provide in larger quantities. Again, unlike the S. acuticeps fry that were very reluctant to give up the Artemia nauplii, the S. daemon fry accepted the introduction of finely crushed flakes and gel diet fines readily.

Water Photograph Fin Nature Organism

Satanoperca daemon

At approximately 10 weeks, the fry were eventually placed (after a few moves involving a 90-gallon tank and the 72) in the 180-gallon aquarium where they had started out in as eggs. The six adults had all been eventually moved to a 275-gallon aquarium. During the move the fry were counted - there were 169 fry. I had lost a few along the way due in large part to the fact that I was not changing enough water in the various grow-out tanks. However, as soon as I caught up on the water changes the mortality stopped. Also, I made every attempt to maintain the extreme water chemistry parameters their parents were originally spawned in, keeping the pH below 5.0. At 12 weeks post free-swimming, the fry had long since developed their black lateral blotches and the pattern of green spots and lines on their heads and were easily 1 inch SL.

The Coveted Demonfish

It is hardly surprising that S. daemon appeals to so many with an interest in South American cichlids. With its bold, black lateral blotches, partially blood-red caudal fin and dramatically produced extensions of the soft dorsal fin; it is a spectacularly adorned animal. However, despite the fact that S. daemon has become one of the most widely-kept geophagines it is still considered problematic to keep and outright challenging to successfully propagate in the aquarium. In fact, since the first published account in 1987 (Eckinger 1987), there have been precious few additional reports. Most cite susceptibility to "Neotropical Bloat" brought on by degraded water quality as the primary reason for the lack of success. Still, after having spent the last decade, and then some, trying to work out the husbandry of S. daemon, I'd have to argue that its a bit more than just large, frequent water changes: appropriate water chemistry and a suitable diet are of critical importance as well.
Eye Plant Petal Tints and shades Font


I like to express my thanks to the following people who have contributed to my efforts with S. daemon: Wayne Leibel, Mike Boyle, Dean Hougen, Martha Clark, Tom Wojtech, Alf Stalsberg, Hernan Fernandez Lopez and my wife Lisa.

References Cited
Bartelme, T.D., 2003. Hypothesis of Head and Lateral Line Erosion in Fish. Freshwater and Marine Aquarium Magazine, 26(9-11).

Eckinger, D., 1987. Nachtsucht von "Geophagus" daemon. DCG-Info 18(7): 132-134

Gargas, J., 1998. A Time-Honored Water Treatment - Peat. Tropical Fish Hobbyist, Vol. XLVII, No. 1 (#511) September 1998: 92-97.

Hemdal, J., 2003. Head and Lateral Line Erosion; what we know about HLLE in aquarium fish. Aquarium Fish Magazine, 15(4): 28-35.

Konings, A., 1993. Enjoying Cichlids. Cichlid Press, Germany. Pp. 240.

Kullander, S.O. and E.J.G. Ferreira, 1988. A new Satanoperca species (Teleostei, Cichlidae) from the Amazon River Basin in Brazil. Cybium 12(4): 343-355.

Newman, L., 2001b. Satanoperca acuticeps (Heckel 1840): The Pointy-Headed Demonfish. Buntbarsche Bulletin 207: 1-11.
1 - 1 of 1 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.