Raising Killifish Fry By Zainudeen Ibrahim
This article is directed towards beginners in Killifish and to those who are contemplating taking up the challenge that these interesting fish generally pose.
Therefore, without much ado, I shall get down to the fundamentals and suggest that beginners would do well to refer to my Book No. 1, under the heading "Introduction", which provides a general background to the keeping and care of Killifish. In it I have indicated the spawning habits, the level in the water at which the eggs are laid and the country of origin for each species and, wherever possible, the common name.
For those wishing to break into this field seriously, I would strongly suggest starting with the genus Aphyosemion, with the two relatively easier species A. gardneri and A. marmoratum, together with the comparatively difficult Epiplatys annulatus. A. gardneri (either the yellow or the blue form) is the easiest to breed. The common name is "Rocket Fish" because there is a red streak stretching from the caudal peduncle right through to the end of the caudal, fin. Keep the male and female separately and feed them live organisms, such as Tubifex worms, Daphnia and White Worms. The breeding tank should be a small one, say 12" x 8" x 8", and I generally cut a piece of polystyrene about 2" square, to serve as a float. Wash some Java Moss and then drape it over the polystyrene float until it touches the floor of the tank. The water should be slightly on the acidic side, say pH 6.6-6.8 and the temperature should be maintained at 24C.
When the pair of Killies are ready, introduce them into the small tank and if they are in breeding condition, they will start to spawn straight away. Aphyosemion gardneri is a "switch spawner' and the above arrangement of Java Moss will allow the pair to start at any level they happen to choose. The floor of the tank should be clean and kept as free as possible of fish wastes and other debris and as soon as the parent fish have finished spawning, they should be removed and put back where they came from. The eggs are generally difficult to locate but with experience of the particular species, one gets to know whereabouts to look for them.
The eggs start to hatch in about 16-20 days but hatching is rather uneven because the incubation period is quite variable and the fry do not emerge at any particular time of day. Frequent partial water changes are then very important and should be undertaken at least twice a day.
Replacement water should be adequately aged before use. I use 2 large plastic garbage bins, fill them with hot water from the tap and leave them uncovered for several hours. Before use, I treat the water with "water agec', obtainable in bottles from any pet store. I also use non-iodised common salt for the prevention of velvet disease (Oodinium sp.), to which Killifish are susceptible, the dosage being 1 teaspoon for salt to every 2.5 gallons of aged water.
Epiplatys annulatus is a very beautiful species but it is a difficult one to maintain. The fish are susceptible to bacterial infection and this can affect the eggs dramatically. Velvet disease can also be a problem but can be checked with the above mentioned salt treatment. Eggs that have obviously been damaged by infection should be removed promptly with a pipette and disposed of by burying and if the problem is a major one, treatment with methylene blue or acriflavine may be necessary.
Microworms may be a little too large for fry,at first, so the altemative of 'green water', which contains an abundance of infusoria, should be used as a starter. Set up a simple drip system to deliver 2 or 3 drops every half hour and use it for a week or so, before switching to Microworms and graded Daphnia.