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Is there a mating season?

What is the suggested tank size?

What should the tank temperature be?

What food should I feed the fry?

And any other things that might be helpful to know.

Unless keeping them outdoors in areas of seasonal variance in temperature similar to their natural home in guatemala, honduras etc, the breeding season is an irrelevance.

Aquaria for breeding should be at least 30-40 gallon, and decorated with large flat rocks on the substrate , the dempseys will clean and then lay on large flat horizontal surfaces. Fine gravel that the parents will arrange to form pits should be provided, once hatched the young will gravitate to, and often be directly put into the pit by the parents, who will periodically round them up , wash them and spit them out into the pit.

Temps will need to be around 27-28c.

The fry are seriously tiny, so it will help if you can procure liquifry or grow your own infusoria to get them started, a little blanched lettuce dropped in the tank will age and grow infusoria, and the parents may well enjoy it too, leaving the young to graze off fragments they adults cant be bothered with .

Then over the coming weeks progress them on to decapsulated brineshrimp cysts, then after about a month they will be taking bits of bloodworm, daphnia, tubifex etc to bring them on in size quicky. They are mainly predatory up to a centimetre long after which time you can start giving them ground and powdered cichlid pellets along with the baby fish diets and tiny livefoods. If you deliver foods to the young over the pit, they will get the best chance to feed, even though periodically the parents will eat the foods, and sometimes remove them.

Be prepared with antifungal agents at hand as the eggs may be destroyed by saprolegnia infections and other fungi before they get a chance to hatch. Eggs will hatch in anything from a few days to over a week.

Try pre-breeding conditioning with bloodworm, tubifex and small pieces of real fish to get the parents in the breeding mood.

Usually the fry are left in the parents care, but other community fish should be excluded, including plecs and scavenger species. They will simply vacuum up the almost microscopic fry, and if the parents are angered may suffer an acute case of being beaten to a pulp. Sometimes covering the aquarium sides with newspaper may help prevent the eggs and fry from being eaten by the parents.

Egg eating behaviour commonly happens if the dempseys think the eggs may be eaten due to disturbance from the keeper, so try not to disturb them when breeding, and keep an eye on progress as discreetly as possible.

Also to ensure you dont lose too many fry to the filter, put some sponge over the intake, or fit a prefilter, or a barrier like ladies tights! It helps to have the filter intake at least 3 inches above the gravel. If you are able to move filter intakes away from laying areas and creche pits, do so.


Good luck with breeding this beautiful species!

Well, here's my situation...
I have two, almost full grown, Jack Dempseys. I always assumed they were male and female because of some research I did to find out the difference. Well, I was not expecting them to breed but sure enough; just the other day I noticed a large amount of eggs on a flat rock in the tank. This, I was not prepared for. My tanks temperature is at room (maybe a little colder) because I never really got a heater for it. The eggs have been there for a day now and the water is not the suggested 27 degrees Celsius. If I go out today and get a heater and set it to 27 degrees will the eggs survive? Also, since I was not expecting them to breed, there is a Cory and a tiny Albino Pleco. If I remove those two other fish will it cause some problems for the present eggs? I think thats it. Thanks!

Well cichlid eggs are sensitive to changes in water temperature, but the higher temperatures are important for the development of the fry. You'll often find that dempseys once they have started breeding, will keep breeding, so buy the heater by all means, but dont put it in for this particular batch, since hiking temperatures now will kill the eggs. Prepare for a long hatching time, perhaps over a week,and a lot of dead eggs, because they will not have matured in the females body at the right temperature anyway and the fertility level of the male might be low.Fry development will be slow too and you may have quite a few losses,indeed if the fry dont look too vigorous the parents may well eat them but a few will probably survive.

After the fry have reached over a centimetre in a month or two, you can put the heater in for next time, and then youll probably experience faster growth and better hatching and survival rates.Dont forget to raise the temperature slowly, try a degree or two a day, dont just put it in and set it straight to 28c if your tank is much cooler than that.You could give the fish thermic shock.

I would move the plec and the cory because although the parents will keep them off the eggs, they may eat the fry, particularly at night when the dempseys cant see too well, and wont protect the fry. Theres also a real chance when the fry are hatched that the dempseys might simply decide to kill the plec and the cory outright to protect their young. Dempseys often have an awesome temper when breeding.

A lot of first egg batches dont go well with many species,keep things as they are for now, and just get the tank ready for their next breeding effort, which may be in as little as a few weeks if they eat the current eggs, and perhaps within 3 months if they successfully raise any of this batch. Expect anything up to 500 eggs when the dempseys are truly mature and kept in the right temperature range. Your two are obviously willing, and thats half the battle.

My eggs just hatched this morning. I seem to have at least 100 babies. Right now they are feeding off the algae in my tank. Have any pointers?

Thats excellent news , for the first day or two they will be living off their egg sac and trying out a little microfauna on the algae, so see if you can get some liquifry or seriously powdered fry food, and see how they go over the next two weeks. If theres no growth or they start to die off, you could try adding a heater and set it to rise by one degree a day until optimum temps are reached, avoid putting your hand near the fry though, as the parents might decide to eat them, try to keep general disturbance near the tank as minimal as possible. Keep the parents well fed too.Aside from feeds make sure you leave them pretty much alone for the next week at least.