Malta Aquarist Society

Killifish are the most widespread species of all fish. They are found in every continent except that of Austrlasia. Here they are replaced with Rainbow fish which are very similar in breeding habits. Killifish are very near to the livebearers. Both these species have teeth and are called egg laying tooth carps while livebearers are called livebearing tooth carps. If you are able to breed guppys( who cannot), then you are able to breed killifish as long as you folow certain rules.

Most killies live and breed in cool water. 20-22C is the ideal water temperature for most of them. Some, like the Aphanius species can be kept outdoors all year round. The Aphanius species are found nearly on evry shore that is washed by the Mediterreanean Sea, the Red Sea, the Middle East and as far as the Persian Gulf. These fish live in either sea water and/or fresh water depending on the species. Most of them are at their best in brackish water (salmastru). These fish will live up to over 2 years provided that their water temperature is lowered down in winter. They will survive even in temperatures of 10C. If kept in warm water all year round, their live span will be much shorter. I have species that have been outdoors for over 10 years and they are very healthy. In winter, their metabolism slows down and they will not even come up for food, but as the weather warms up and the water temperatures start to rise, they colour up and spawning activity begins. They will keep spawning until the water temp. raises to 28C. Their eggs are are large, around 2mm. and hatch out in 8 to 12 days depending on the temp. and will eat newly hatched brine shrimp at once. Growth is very fast at first but when the fry reach 1cm., slows down.

The Aphyosemoins are probably the most colourful fishes in the world. These come mostly from West Africa and again, if kept in cool temp. will live up to 2 years. The ideal temp. for the Aphyosemions is around 22 to 24C. Over 28C. is critical and most adult fish will die. However, young fish will survive the heatwave and one can carry on breeding from these young fish in autumn. The eggs of these species hatch out in around 14 days. Growth is fast and in most species, these are will start to sex out at 6 weeks. At 3 months, they will  start to breed.

From East Africa, we have the Nothobranchius species. These are annual fish, that is, their live span is only a year or less. This is so, because the pools that they inhabit, dries up completly in the dry season ( similar to the water holes that we have locally) Their eggs remain dormant in the bottom debris and when the rain comes again, some of these eggs hatch out. Some other eggs will need another dry period and after the second or even more wettings will hatch out. This is why they have survived for so many many years. Growth is extremely fast and in 6 weeks, the are spawning again. Fry from the Nothos. are extemely small and will eat only micro-worms for the first couple of days.

From the U.S.A. we have the so called native fishes. These include the Fundulus species. These are very similar the the Aphanius, both in shape, colour patterns and spawning habits.

Central America and the north of South America is the home of the Rivulus species. The  female of these species are easil recognized from the prominent black spot at the top of the caudal fin. all of them are cylindrical in shape. Their eggs are large, 2 to 2.5mm. Most eggs are foung at the waters edge, dome even out of the water. They take a very long time to hatch, 21 to 45 days. Fry are very large and have huge apetites.

Here too is the natural habitat of the Simpsonicthus and Cynolebias species. These are also annual fishes similar to the ones from East Africa.

Why are these lovely colourful fish not available in lfs? The reason is that so far no one have found a method to produce these fish in commercial quantities. These fish produce a few eggs daily and by time that the fry are a week old, they will eat their own siblings that are hatching in a week later.

So who can breed killifish? Anyone can do so. One have to bear in mind that killies are carnivorous fish and have to be kept on their own. Females from most species are difficult to tell apart, resulting in cross breeding and hybrids which are sterile and the species will be lost. Small tanks, even large jars are good for a breeding pair. These should be covered at all times as the fish will jump out. A few floating plants or nylon mops should be provided for the pair to lay their spawn in and also as refuge for the female. Eggs are either left with the pair and a few young will appear in over 15 days, or else the eggs are collected daily and water incubated in margerine tubs. After the eggs are fertilised, their shell hardens and will not break if picked up gently with your fingers. These eggs will hatch in 14 days and if the eggs are stubborn to hatch, a water change and the addition of a drop of micro-worms will do the trick. They can be kept in the margerine tubs for 2 weeks, provided that regular daily water changes are made.

Breeding annuals is for the more experienced breeder. I will deal with these later. In the meantime, I am going to include some photos as I believe that the more aquarists see these fish, the more interest will be generated. Killifish can be obtained  in pairs from local breeders or else imported as eggs from any part of the globe.

As I had already posted some photos in other parts of this forum, I will not be repeating these photos. Anyone interested will look for them  under the title australe.

2nd Part of the Article

. Annual Species

As I wrote in the other write-up, to breed annual species, one have to be an  aquarist with some breeding experience with egg laying fishes. We have annual killies from East Africa, the Nothobranchius that spawn on the top of the mud and dead debris and also the divers from South America. These are the Simpsonichthys and the Cynolebias. When spawning, the pair of these species, dive head first into the bottom mud and burry there eggs in the bottom. Annual killifish, usually are more fertile when compared to plant spawners and spawning will take place from the moment that these fish become fertile, till they die. For this reason, it is important to segregate the sexes. By nature, the females are much smaller than the males and if keep together, they will start to spawn before they are fully developed and none of these fish will reach a decent size.

To copy   the natural conditions, we hobbyists, use peat as a spawning substrate. It is advisable to use coarse peat  that  had been submerged in water for a number of weeks. This is to remove as much as possible the tanning effect from the peat. If very fine peat is used, firstly, it would be difficult to see the fish and later, most of the eggs will not hatch out and die. Eggs need oxygen to develop and if the peat is very fine, it will inhibit the circulation of oxygen, the embryo will not develop and the egg will die.

In nature, these eggs remain without any visible development until the pool dries up during the dry season. Then some of the eggs will start to develop while others remain transparent. From the eggs that start to develop an embryo, some will hibernate (diapause 2) for some weeks or even months, while others will develop into a ripe embryo and hibernate as a resting fry (diapause 3). So, when the pool is dry, there are three types of eggs. Eggs that are ready to hatch (daipause 3), eggs that are as resting embryos (diapause 2) which will continue to develop after the pool dries up again and eggs that have not yet started to develop and will need several more wet and dry periods to trigger them from their hibernation (diapause 1)

If the first rain of the season is a small one, the fry that hatch out will not have time to become adults and start spawning and so these will die without leaving any offspring. But the next dry period will trigger the development of the eggs that are in diapause 2 and when the next rain comes, it will be their turn to hatch. This process keep in action for several wet and dry seasons and may last up to 5 years.

As I said above, we use coarse peat  that  have been soaked in water for several weeks or months. The pair are heavily feed on live foods and then introduced into a small tank with the bottom covered with peat. If you are to use a large tank or breeding peat divers, a margarine tub can be used. Put some glass marbles in tub and add peat to about half of full. Cut a small hole in its cover, big enough for the pair to be able to enter into the tub and put it in the tank. Breeding will start very soon. After a week, drain the peat through a very fine net, remove the glass marbles and let it drain for a couple of hours. Then put the peat on top of a couple of newspaper sheets, roll it up and leave it to dry for around 24 hours, depending on the warmth of your fish room or the season. Afterwards, the peat with the eggs in it is placed in a polytene bag and tied up. This is then labeled with the species name, estimated hatching date and stored in a warm,( above 20C.) in a dark place. When the date comes for the eggs to hatch, empty the peat in a small container and add filtered rain water that is a little cooler then that the eggs were stored in. A gentle current of air and a drop of micro-worms will smooth out the operation better. In  a  few hours you will see the fry swimming around. At first, they seem to be all deformed, but most of them will straithen up and be normal the next day. Usually, hatchings  are very large and although fry from most annuals are very small, growth is very fast. In 6 weeks, many species are ready to start spawning. Sex ratio is usually, mind  boggling. Once from a brood of around 200 fry, only 4 were females.

Disease:  As I said that it is better to use rainwater to hatch annual killifish eggs, most of the diseases thrive in this water. One disease, called Mycobacteria, if not controlled will wipe an entire hatching in a few days. If the fry, a few days after hatching are transferred to hard alkaline water (our tap water is perfect), the attacks from this disease will be less serious.

Again, velvet disease or Oodinium are less active in hard water. Mycobacteria live inside cells containing fat and attacks from this disease occurs on juveniles that are about to become sexually mature, as at this stage of development, the gonads contain a lot of fat. The gonad is the animal organ that  produce gametes which is the sexual cell. The best way to prevent this disease is by using hard water and regular water changes.

Once the fry are past this stage, growth is very fast and at 6 weeks, most of the males are in full colour and chasing the females to spawn.

As for water parameters, do not worry too much about it. Most killifish adapt and are happy in many types of water. I do not have a test kit, so I do not know exactly what type of water I have. For hatching, I use filtered rain water ( ilma tal-bir), and for rearing I use filtered tap-water. There are two ways to let you know if your fish are comfortable or not in your tanks. The first one is” Are your fish always hungry and asking for food? If yes, then they are in good condition. The second one is to add apple snails to your tanks. When the apple snails are out of the water most of the time, then your tank needs a water change. Apple snails are more sensitive to water pollution then fish are, and usually will die before most of the fish.  If  the  apple snails are dying and the fish  refusing to eat, then your tank and filter need a clean up.

  One last  advice. Be careful about using water from bore-holes. Usually, this water is very salty and might also contain nitrates and other pollutants. About 8 years ago, a friend of mine from the Rabat/Dingli area, came to my home thinking that the test kit that he just bought was not functioning properly. He was using water from a very old bore-hole (spira) and to his surprise, he found out that his water was very much harder ( dH.25) while my tap water was reading 20. Many pesticides and fertilizers that the farmers use, will finally seep into these bore-hole and if this water is not professionally treated, it will cause a lot of harm to our fish.  

This is Aphanius dispar from Fallujah, Iraq.

Aphyosemion australe (chocolate)

Aphyosemion striatum

Fp.sjoestedti

Fp. gardneri Misaji.

This species was bought from the BKA convention last October.

Ps.annulatus from Sierra Leone.

More photos will follow soon.

 Informative article Charles .. hope articles like yours will encourage more fish keepers to start breeding killifish.

Thanks, Charlon. I appreciate your support very much. I would also like to thank Corydoras seracin for his positve comments. I believe that if we keep showing our members how beautiful killifish are and that it is not that hard to breed them, then more aquarists will be joining us.

Charles and Charlon I am sure with such photos and explanation others will follow, thanks for such information and excellent photography.

Thank you Mr.President and Congratulations too.

As soon as I have time to type the second part regards breeding of annual killifish, I will do so. 

Yes Mr. President, Congratulations Charles Grima.

Thanks Charles Zammit. These fish have the nicest colors i have ever seen.

One day I will buy some from you hopefully. but for now I need to get to my house cause at my mums I have no place and she is going to throw me out! together with my aquariums :)

Here are some more photos. These are fry off A.australe (gold) 1 week old. The other photo shows the same fry enlarged. Note the small apple snails. These

will eat the uneaten dead brineshrimp but will not eat any fry.

The following photos shows Aphanius dispar Richardsoni Ein Feshka, Israel.These photos are reproduced by kind permission of Barbara Nicca from Switzerland. She is very keen on Aphanius species and had travelled to the Middle East on collecting trips.