April 26, 2009
INFORMATION ABOUT THE CARE OF JACK DEMPSEY CICHLID FISH
INFORMATION ABOUT THE PROPER CARE
OF JACK DEMPSEY CICHLID FISH
The Jack Dempsey fish, an aggressive and strong cichlid, is named after former heavyweight boxing champion “Jack Dempsey” who shared these same characteristics. It is a very hardy fish that is easy to care for, but due to its aggressive temperament, is not recommended for novice aquarists. In Spanish speaking regions in Central America where the Jack Dempsey is native to, it is called Mojarra Castarrica or Riquiraqui. The scientific name is Archocentrus octofasciatum. The species forms a part of the genus Cichlasoma in the Cichlidae family.
Wild Jack Dempsey cichlids can be found in North and Central America where they inhabit a region that stretches from the Papaloapán River in southern Mexico to the Hondurian Ulua River in Central America. The Jack Dempsey cichlid is often found in muddy canals, drainage ditches and swamps since it appreciates murky and slow flowing waters. In the coastal plains of Central America you will find warm and slow moving streams that are ideal for this cichlid. Since the wild Jack Dempsey cichlid lives in waters with a muddy or sandy bottom, it is naturally a good idea to use such substrates in the aquarium.
Today, the Jack Dempsey cichlid has been introduced to waters outside its natural region by man. You can therefore find breeding populations of Jack Dempsey cichlids in the United States, Australia and Thailand. In Thailand, Jack Dempsey cichlids are produced in aquacultures for the aquarium trade. From these aquacultures, Jack Dempsey cichlids have frequently escaped into the wild since the first Jack Dempsey aquacultures were established in Thailand during the 1950s. In the United States and Australia, the Jack Dempsey cichlid populations most likely originate from specimens released by aquarists. The warm waters of Florida are today home to a wide range of tropical aquarium species from all over the world, including the Jack Dempsey cichlid. In Australia, the most notable Jack Dempsey populations are found in out-flow creeks in the state of Victoria and in cooling ponds used by a power plant. The Australian Jack Dempsey cichlid populations are however showing signs of decline.
The Jack Dempsey cichlid is not included in the IUCN Red List of Threatened Species and you can find thriving populations of Jack Dempsey cichlids in its native region. Since its minimum population doubling time is less than 15 months, it is resilient towards over fishing. In the aquarium trade, the commercially bred Jack Dempsey cichlids are common.
As mentioned above, the Jack Dempsey cichlid is easy to care for in the aquarium but considered unsuitable for inexperienced aquarists since they might find it difficult to handle its aggressive temperment and counteract violent behaviors. Jack Dempsey cichlids are often kept in their own aquariums instead of community aquariums or habitat aquariums, but you can keep this cichlid with other species if you select tank mates carefully. Avoid standard community aquarium species, since they tend to be peaceful and will become bullied by the Jack Dempsey cichlid. Aggressive species of similar size that can fend for themselves is a much better choice. Avoid keeping more than one Jack Dempsey cichlid in the aquarium, and avoid species that look similar to the Jack Dempsey cichlid since they may be perceived as enemies by the Jack Dempsey cichlid. It is also very important that the aquarium is large enough for the Jack Dempsey cichlid, and decorated in a way that makes it possible for the cichlid to claim a limited region as territory.
Arranging a suitable home for a Jack Dempsey cichlid will require some dedication from the aquarists, but it is well worth it since the Jack Dempsey cichlid is an energetic and extremely beautiful fish that will add action as well as color to the aquarium. It will also adapt to most water conditions, so it is really not difficult to keep once you have learned how to master its aggressive temperament. In a well kept tropical aquarium your Jack Dempsey can live for 8-10 years.
One way of calming down a quarrelsome Jack Dempsey cichlid is to keep the water temperature down. The recommended temperature range for a Jack Dempsey cichlid is 72-86° F (22-30° C), but many aquarists make sure that the temperature never goes above 78° F (25.5 degrees C) since warm water can increase the aggressiveness in some Jack Dempsey cichlids. Regardless of temperature, the Jack Dempsey cichlid will always claim its own territory and defend this part of the aquarium. As mentioned above, the Jack Dempsey cichlid can adapt to a wide range of different water conditions. The preferred pH range is however 7.0-8.0, and the dGH should be kept between 9 and 20.
An adult Jack Dempsey cichlid can grow up to 10 inches (25 centimeters) long and must be provided with plenty of space. Do not house it in an aquarium smaller than 45 gallons (170 liters). If you plan to keep it with other fish, the recommended aquarium size will naturally depend on these species as well.
In the wild, the Jack Dempsey cichlid inhabits densely grown waters. Plants are however often avoided in Jack Dempsey aquariums, since the Jack Dempsey likes to eat live plants and can destroy them. You can instead use flowerpots, caves, rocks and wood to form natural borders in the aquarium and make it possible for the Jack Dempsey cichlid to claim a limited territory. Since the Jack Dempsey cichlid is fond of digging, you should avoid substrate with sharp edges. A barren bottom, or a very thin substrate layer, is also inadvisable. Heavy objects that can injure fish if they fall should be placed directly on the glass, since they might fall when the Jack Dempsey cichlid digs around.
You can usually train a Jack Dempsey cichlid into accepting most types of food, but it might take some time before the fish realizes that a new food type is actually edible. When a Jack Dempsey cichlid has understood that what you give it is actually food, it will usually be a happy eater. The wild Jack Dempsey cichlid feed mainly on insects, worms, crustaceans and fish and will appreciate such food types in the aquarium as well. Flake food and pellets can also be used; but pellets are usually a better idea since flakes are a bit too small for large Jack Dempsey cichlids. A high-quality pellet can be a good base for the Jack Dempsey cichlid, but should ideally be combined with occasional treats of live food. Fish, earthworms, grasshoppers, shrimps, crayfish and small frogs are just a few examples of live food that your Jack Dempsey cichlid will like. When the Jack Dempsey cichlid is kept in an unplanted aquarium, it will need some vegetable matter in its diet, e.g. lettuce and plankton.
If your Jack Dempsey cichlid suddenly changes its coloration, the alteration can have been caused by a number of factors. Sudden changes can be caused by mood swings, and stress can also make the Jack Dempsey cichlid dampen its colours. A varied and nutritious diet is also necessary if you want your Jack Dempsey cichlid to display really great colours. Age and health will also affect the coloration of a Jack Dempsey cichlid. If your Jack Dempsey cichlid becomes ill or experience a lot of stress in the aquarium, it can turn much paler than normal and look dull. The dots and bands will be less visible. A healthy, adult Jack Dempsey cichlid will typically feature a strong purple coloration with shimmering spots of blue, green and golden. You can clearly see a dark dot on each side of the body and tail, and the dorsal side features dark bands. If you closely at one scale, you will notice green or yellowish spots against the darker background. In older specimens, these spots will gradually become less visible. Really young specimens on the other hand will not have the purple coloration of the adult Jack Dempsey cichlids. Young Jack Dempsey cichlids are camouflaged by a pale grey or tan coloration, and have bleak turquoise dots. The mature male Jack Dempsey cichlid differs from the female, since the ends of his anal and dorsal fins are elongated and pointy.
The Jack Dempsey cichlid is commercially bred in aquacultures and it is also possible to breed this cichlid in aquariums. It is considered a moderately hard species to breed in aquariums, and breeding Jack Dempsey cichlids will always be extremely aggressive. The Jack Dempsey cichlid will typically reach sexual maturity when it has grown to approximately 7-8 inches (18-20 centimeters). As mentioned above, many aquarists choose to keep the water temperature down in the aquarium to reduce hostile behaviors in the Jack Dempsey cichlid. If you want to spawn your Jack Dempsey cichlids, an increased temperature is however recommended. Breeding Jack Dempsey cichlids should always be kept in their own tank, or in an aquarium divided by glass or net, since the parents are extremely aggressive during the breeding period.
The Jack Dempsey cichlids will appreciate a breeding site in the aquarium in the form of a flat rock. The female Jack Dempsey cichlid can however deposit the eggs directly in the bottom substrate if there isn’t a flat breeding site around. The adult couple should not be removed from the aquarium when the eggs have been deposited, because they are devoted parents that will care for the eggs. The parents will also dig a pit in the substrate in which they will place the larvae as soon as the eggs hatch. As the fry grows older, the parents will continue to protect them and care for them. The adult Jack Dempsey cichlids will even pre-chew food for their offspring as long as the young ones are too small to eat normal food. ♦
Written by: Jack
Filed Under: General
Tags: Add new tag, care, cichlid, dempsey, fish, jack, maintenance
derek kearns
August 1, 2009 at 5:33 am
looking to keep jd with green terror u reckon they be fine two males 240 litre tank or maybe a texas ciclid with the jd what u think?
Mathew
August 6, 2009 at 12:24 pm
I have a pair of Jack Dempsey’s and it spawned 3 times in the last 7 months. Last week Dempsey’s ate all of their babies. Do you know why?
Barbarann
January 18, 2010 at 9:54 am
This has happened a few times with our fish as well. I have 2 mature JD’s and they have been a pair for as long as I have had them – i took them in when it’s previous owners had to move out of state. This was about 3.5 years ago. I knew very little about thier breeding habits and was very surprised to see tiny little semi translucent eggs deposited on the rocks. A few days later, I had my wigglers and was thrilled. My kids were thrilled as well and had thier faces pressed up to the glass half the day to see the fry.
What we didnt seem to pay attention to though, was the adult female charging towards our faces and puffing up her gills !
within a few short day all the fry were gone and we didnt kmnow why. It was a good year or so before they had more fry. this time I started to frantically search all over the internet as soon as the eggs were deposited … looking for ways to ensure these fry would survive. Never did I suspect that the parents had eaten thier babies- I assumed they just died and mysteriously dissapeared somewhere. These fry lasted a wee bit longer- we went on vacation 2 days after they were hatched- unfortunately the pet sitter ( for my cats and fish) wasnt paying a whole lot of attention to my fish care instructions, she WAY overfed them – I mean WAY overfed them- their entire 10 oz.container of pellets was dumped into that tank in a week- when we got home we were horrified to see the tank so filthy and the water so brown and cloudy that we could barely see our 2 mature fish, so I am pretty certain that the water quality is what did it that time…. next time was about 6 months ago. We had a pretty successful run, and after about 4 weeks we had 5 fry left- robust and healthy. we were looking into getting them their own tank, but we were too slow and by week 5 just one remained. this is around the time that momand dad fish had more fry. mom and dad became super agressive towards my singular young fry that was left. I mean, really really aggressive. to make matters worse, my kids had themselves parked a few inches in front of the glass, again to watch the new fry . within 24 hours of the new fry hatching they were all gone- EATEN by mom and dad!
I was horrified! as it turns out, 2 factors were involved. the first one, the kids were aggitating them- and making them feel extra territorial and extra protective – thats why the momma fish was charging at my kids faces.. and puffing up her gills-she looked at them as a threat to her new fry.. and having the older fry in there was a threat too which is why the parents were being so aggressive (if not homicidal !) towards the one remaining older fry. As it turns out, feeling very threatened can cause so much hostility and agression that the parents will actually eat thier own fry. I am thinking that the first fry that they ever had ened up being eaten as well because of all the extra attention that was being givin via my kids having thier faces pressed against the glass constantly!
Dave
August 26, 2009 at 7:27 pm
Brilliant write up Jack, I have been researching Jack Dempsey’s for some time now, This is the best I have seen so far.
Very informative and easy to understand for the reader.
Thank you.
Sharyn
September 13, 2009 at 10:01 am
Why do they bite each other? I have 4 jack Dempseys and one of them always chases and locks lips with another one. Poor fishy looks stressed! Why do they pick on that one? Please help!
Gene Saunders
September 21, 2009 at 11:34 pm
My favorite fish. I have loved these since the 1960’s. I used to have a male Dempsey that I kept in his own tank. He would “dance” around excitedly whenever I came into the room and jump 1/2 inch out of the water to take food out of my fingers! Very beautiful, very smart, and very hardy fish, but not recommended to be kept except with other large Cichlids.
Amber
November 18, 2009 at 7:37 pm
This article makes the raising of a Jack Dempsey sound very difficult. Had I read it before purchasing mine, I might have selected a different species and missed out on a great fish. I don’t intend that as criticism. Readers should be aware that many of the statements are generalizations; don’t be afraid to take on a JD.
I am a complete novice when it comes to Cichlids; my partner is nearly so. About ten months ago, we bought a couple of Firemouth Cichlid–about 2.5 inches long–and put them in a 29-gallon tank with rocks, wood, and a heater. They did very poorly for the first several weeks, spending most of their time cowering in the bottom of the tank and barely eating. We installed a pump on the undergravel filter and an aerator, and we added a few other non-Cichlid fish. One of the Firemouths died, and we replaced it with a JD.
The JD was very aggressive from the moment we put it in the tank, and it dominated the other Cichlid. We had read that Cichlids would establish territories, and we thought that perhaps our Firemouth was a defective fish, so we then added a Green Terror. The GT turned out to be “defective” too. Long story short, over the months we have cycled through many fish, but that JD has persisted and is now 7+ inches long. Nearly all of the other fish we’ve added have disappeared (probably down the JD’s gullet), but the JD is still going strong.
I acknowledge that our tank is on the small size and will eventually need to be upgraded, but for the time being it seems to be sufficient. The JD shares it with a 4-inch Plecostomus, and they don’t get in each other’s way. The tank has several plants in it, and the JD has not molested them. In addition to the undergravel filter, heater, and aerator, the tank is equipped with a waterfall filter. I change about 5 gallons of water once a week.
The JD is very active and appears healthy. His diet consists of brine shrimp, earth worms, and the occasional scrap of chicken, beef, or mussel; he consumes everything with gusto and does not require any time to acclimate to new food items. He bites fingers and test-strips and anything else that is introduced suddenly to the surface of his tank.
This is my first and only JD; perhaps he is abnormally robust and intrepid. I think that the bottom line is that JD’s are not hard to raise as long as you give them plenty of space to themselves; don’t expect to have a diverse community tank, and don’t expect a JD to behave itself in mixed company. They don’t necessarily require a mondo tank, and you shouldn’t be afraid to add plants. Just keep the JD’s tank clean and warm, and don’t get attached to any other living things that you add to it.
paul miller
January 13, 2010 at 10:50 am
i myself am torn between three fish as my favorite, the depsey ,red devil and last but certainly not least the red tail catfish. i will say dempseys and red devils do make a hell of a pair as long as u get them young and around the same size the red devil is a tad more agresive but dont evr put them in with the cat they eat everything my red tail ate two full grown oscars before i got him out of my tank leaving me with only my dempsy red devil and red belly paranah in a 250 gallon tank but for a dempsey u want to get big fish and very agresive fish and hope for the best they like their space but red devils are a good way to go it makes for a very active tank i will tell u that lol