Breeding Fact Sheet No. 11

Winning with Nothobrancius guentheri.

It was over twenty years ago that I purchased my first killifish, I had just completed work on my first fish-house and went out to buy some fish at a shop that was owned by fellow Tonbridge & District Aquarist Society (no longer in existence) member Brian Price.

I had some small tanks ready for Killies and as luck would have it Brian had quite a few species that he wanted to get rid of as people were not interested and they were taking up valuable tank space. I left the shop with a smile on my face having purchased some heavily discounted fish, including; Aphyosemion bivitatum, A.australe, A. australe (gold) and one or two others.

Moving on twenty years later, now with a new fish house (and family), I visited Swallow Aquatics in Essex and purchased a really nice pair of Nothobrancius guentheri. I wanted to breed them so asked Pete Cottle for advice. The method I use is exactly as Pete advised and I can see no room for improvement.

The fish are kept in a 13"x12"x15" with Kent tap water (very hard and often with a PH in excess of 8!). The tank is filtered using a small sponge filter and there is no substrate. The tank contains a large amount of java moss, floating hornwort and duckweed. A small margarine tub is ¾ filled with peat (pre-soaked to ensure it sinks), the lid is left on but a reasonable size hole is cut out to allow access by the fish. The tub has to be carefully placed on the bottom of the tank after releasing as much trapped air as possible. A certain amount of peat is released into the tank, the water sometimes becomes cloudy, but this soon clears. A pebble is placed on the tub to ensure it doesn't float.

The fish soon begin to explore the tub and it isn't long before spawning commences. The tub is left for about two to three weeks and is then removed and the peat emptied into a large net. The peat is squeezed very hard, leaving it just slightly moist. The peat is then checked for eggs to establish how prolific the pair have been.

The eggs are slightly under 1mm in size and appear in the peat as dark amber in colour. They are quite sticky and care is needed to ensure no eggs are left in the net or stuck to your hands!

The tub is refilled with fresh peat and placed in the tank as before. The peat containing the eggs is put in a plastic bag which is labelled with the species name (and if more than one pair are producing eggs, I like to know what pair the eggs are from) and also the date the peat was dried. The bag is then sealed and stored. I store my eggs indoors at room temperature, but they can be stored at higher temperatures.

After three months the peat containing the eggs is placed in a small tank containing a few inches of water taken from the tank which will be used for growing on. At this point I would mention that eggs kept at high temperatures may, apparently be hatched after just one months storage, this is something I haven't tried.

Within a couple of hours the first fry emerge and need feeding almost immediately. I feed liquifry and microworm about four times per day for the first few days. The fry then need to be moved into a larger tank, I tend to put them in the same type as their parents, i.e.: a 13"x12"x15", but with just a few inches of water, sponge filtration, no substrate and a few snails to eat leftover food and dead fry (my and other's experience are that losses are very high, I don’t yet know why).

Just a note on the filter, to enable a filter to work efficiently in very shallow water, I cut the small Algarde type down to about half size, this even allows them to be used in the smallest of show tanks.

The feeding of Liquifry is stopped after the fourth day and powdered flake is substituted. Once the fry start putting on size, they are fed frozen artemia and Cyclops. After another couple of weeks, chopped tubifex and chopped frozen bloodworm is fed. As soon as the fry can take live tubifex a quantity is placed in their tank as per the adults. Once on tubifex, the fry put on reasonable growth and a good body shape develops.

The young males have to be carefully observed and as soon as they begin any form of aggression, they must be split up in order to prevent fin damage occurring. Once the males approach their show size (currently 45mm SL.) they are carefully inspected and the best one or two are selected as show fish. I have always found N.guentheri to be superb show fish as they are as happy in a show tank as in their stock tanks, in fact I have shown pairs and they readily spawn while on the show bench!

At the 2001 FBAS Supreme final I had an excellent result when my guentheri achieved 3rd place, but this was nothing compared to the shock I received the following year when one of his offspring came 1st. As for the 2003 finals, it was unfortunate that I was unable to make an entry into the class F (Killifish) championship class, as the qualification show was at the beginning of the year (We are talking about an "annual" fish, so it would not live to see the supreme!). I have the same dilemma for the 2004 event. Would a guentheri have got a place for a third year? I'm not so sure, there are some superb fish currently being shown, so maybe not.

I intend to carry on showing guentheri until they stop winning the killifish classes. It's been great up to now!

I hope this short article has provided some inspiration and shown that with the most basic small tank and a little patience, a Supreme winner is within the grasp of any aquarist should they so desire.

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