Killifish Breeding : Progress with Aphyosemion celiae July 2017

Aphyosemion celiae is an endangered species of killifish, known from two localities close to each other in Cameroon. See my video on food and localities here: Our local water is similar to the water in their natural habitat, since both flow through volcanic rocks (basalts) and laterite (red clay) soils. We use a common water source for all eggs and fish, a cycled 55 gallon tank with plants, fish, and snails. 

A 55 gallon cycled tank for common water

Twenty gallons are used for water changes every week.  Dried Indian Almond Leaves tint the water and reduce bacteria and fungi.

A. celiae will lay eggs on synthetic mops. We have two mops for each pair. Symbols specific to each pair are written on the cork with magic marker.

A rack for mops, two per pair, with a species ID on the cork

The male watches for Drosophila

A mop dipped in boiling water. It will be cooled in stock water before use.

Before picking eggs from a mop in the 2.5 gallon breeding tank, we wash a replacement mop with tap water. Next we dip the replacement mop in a Pyrex pot of boiling water, then cool it with common water.
We put the cooled second mop in before removing the old mop with eggs. This reduces stress in the fish, as it provides shelter during the disturbance.


With heavy feeding and a water change from the common water, the female watches the male's courtship dance and follows him into the mop.

Our female colors up as she watches her mate's courtship dance. There is a video on my YouTube site here:  https://www.youtube.com/watch?v=xLD62PIoat4

Start, then click the box lower left to enlarge

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Later we will have a video on water changes. Notice from the picture we don't use filters in the 2.5 gallon intensive breeding tanks, instead we rely on weekly 80% common water changes. If the breeding tanks need cleaning they are partially emptied, placed on the bench, the fish are netted with a soft net and placed into an already cleaned and scalded replacement tank with common water and mops. The old tank is scrubbed with a plain plastic pad, rinsed with very hot tap water  (110 F), Scalded with boiling water,  dried with paper towels, partially refilled with common water, and a  clean mop added when needed. This procedure resulted in the courtship depicted above.

The eggs are placed in glass petri dishes with stock cycled water, i.e. “common water”. In the case of A celiae, we add a few drops of a stock methylene blue dilution, made with 10 drops of Methylene Blue per gallon of water. ON SOME BROWSERS CLICK 2X

A glass Petri dish holding half the eggs from one mop.
Note the letter C marked from the underside, code for A celiae

We gently pull the eggs away from the yarn, then drop then into the water. The photo shows seven A. celiae eggs collected from a small mop on 25 July 2017. Notice that three of the eggs are darker. When the eggs are near hatching, you can see the eyes.

The cover glass gets a paper tape label, including the species code CEL for A. celiae, the number of eggs circled, and for A. celiae, the letters MB for methylene blue.

The eggs are checked once a day, and infertile eggs are removed. About half the water is removed and replaced with common water using a disposable plastic transfer pipette.
Below two A. celiae fry have hatched. The remaining eggs are “eyed up”.

Click to enlarge.Some "eyed up" eggs and two hatched fry.

When they hatch, fry and eggs are moved to a Pyrex bowl in stock water, and labeled. Then the eggs are returned to their petri dish. In a few species the fry are slow enough to  catch with a blunt eye dropper, for example here:  

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The second day the fry are fed newly hatched brine shrimp.

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When they get big enough to jump out of the Pyrex bowl, they are transferred to labeled mini Critter Keepers.
Note the salmon colored bellies, full of brine shrimp nauplii.

Perhaps you would like to count the fry? Try the video:

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