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Food for killifish
Killifish are not often commercially available. Usually only a few known species are available. Many killifish require live food, they like to jump and they are not necessarily suitable for community tanks.
But they are interesting and versatile fish. Many species can be kept outdoors in summer, not just the well-known Eurasian species.
There are beautiful African killifish that do not like temperatures above 22°C. Such species are rarely kept, because only a few aquarists can provide suitable conditions.
Depending on the species, killifish can live up to 5 years. The so-called annual species are a maximum of 12 months old.
In some species of killifish, the eggs need time out of the water to develop. When the required break has elapsed and there is time for hatching, the eggs are put back into the water. The young then hatch after about 4 to 5 hours. The young can be fed Artemia nauplii.
Water parameters for killifish
Fundulus majalis female (horizontal stripes) Source: Image on Wikimedia Commons License: CC Attr. SA 3.0 Author: Steven G. Johnson
Depending on the species and area of origin, killifish require biologically and chemically clean water. The water may only be slightly contaminated with waste materials. It should generally be soft to medium-hard and slightly acidic.
The water should be soft or medium hard. For most killifish the pH should be in the neutral range around 7 or slightly acidic.
Basically, killifish are easy to keep and like to reproduce. About 1/3 of the water should be changed regularly. Slightly lower temperatures than normal in the aquarium should increase life expectancy.
Problems can arise when moving to other aquariums. Killifish should be acclimated slowly. Normally, killifish will eat all types of food from live food to flakes, tablets, etc.
Fundulus majalis Male Source: Image on Wikimedia Commons License: CC Attr. SA 3.0 Author: Steven G. Johnson
Killifish are not aggressive. They can be socialized with other species.
Some species can be kept in relatively small tanks.
Of course, there are exceptions to this general information.
Some killifish only eat live food, etc. Some species may eat the fins of other fish.
Larger species, e.g. B. pike, are well suited to limit the offspring of other fish species.
Depending on the individual and their hunger, they also dare to fish the size of smaller guppy males.
Lucania Parva Source: Image on Wikimedia Commons License: CC Attr. SA 3.0 Author: Richard A. Ingebrigtsen
If several males are kept together, depending on the species, the males may pull their muzzles as a fighting behavior. Usually there are no injuries.
If there are matching females for males, biting can occur between the males and females.
In the case of pike, violent disputes can arise, especially at the beginning of the courtship display.
Any injuries that may result must be closely observed, because according to some reports, wounds in killifish easily fungus.
Killifish jump in and out of the aquarium
Jumping is part of the escape behavior of many killi species, especially when there is no protective cover of floating plants. They usually jump along the surface. But you will also find holes and crevices.
Jumping can be triggered by foreign fish, territorial fights, etc. In the case of Aphysemion gardneri, it seems that the males particularly like to jump. According to a report, out of 100 young animals, after a while there were almost only females in the tank. Most of the males lay dried up behind the pool.
There is evidence that all killifish jump, including species that would not normally be expected to do so. They jump through the smallest cracks.
Aquariums for killifish should therefore always be covered.
breed
Peat and other spawning substrates for killifish
Killifish need a substrate in which to spawn. Peat is often used for this. Filter peat from the aquarium trade or unfertilized peat from garden supplies can be used. The soft fibers are desired, not the ingredients.
In breeding tanks that are not too large, the peat can be planted in a 6 to 10 cm layer on the bottom, e.g. B. fine sand, are placed.
A ball of peat about the size of a fist is usually sufficient. The killifish look for the best place in the tank to spawn and usually find the peat. A peat ball should not be bundled in a net to prevent the fish from becoming entangled in the net. In addition, they can then better dive into the peat.
Some keepers use fine-grained peat, others use long-grained peat. Long-fiber peat is considered better because fewer small parts get into the aquarium and float in the water. The peat must be boiled well, for about 10 minutes. The peat is then rinsed well so that the finest pieces of peat do not get into the aquarium. To do this, the peat is rinsed under running water until the water running off is clear.
The remaining fibers sink to the bottom and do not float around in the pool. However, peat acidifies the water and stains it. The water turns brown or yellow. The color of the water depends on the type of peat and the amount of peat.
Peat can be used as a bottom in small 10 liter tanks, in which the fish are only used to spawn for a few days. After spawning, all the peat is removed with the eggs.
The peat can also be placed in the aquarium in a small plastic tray. In this way, the peat can be changed weekly.
Killifish also spawn in other substrates, e.g. B. Java moss. The foliage of some tree species also offers suitable hiding places.
Coconut soil or unfertilized coconut briquettes can also be used. Coconut soil sinks faster when poured on and thus releases the water surface. Coconut moss also dries faster than peat. Coconut soil is available in garden centers or if needed for terrariums.