Category: GCKA – Breeding Fish

We all know the concerns of going away and leaving our fish: what if some emergency happens while I’m gone? Will they be all right without being fed?         Most experts agree that adult fish can manage quite well for up to several weeks without being fed, as long as their water and temperature conditions…

After extensive effort, you’ve finally succeeded in spawning and hatching out fry from that “special fish.” You’ve even successfully raised a number of them past the wriggler stage and into juveniles. You’re expecting the more or less normal sex ratio of 50/50.         But whey they sex out you have almost all males – or…

   After extensive effort, you’ve finally succeeded in spawning and hatching out fry from that “special fish.” You’ve even successfully raised a number of them past the wriggler stage and into juveniles. You’re expecting the more or less normal sex ratio of 50/50.         But whey they sex out you have almost all males –…

By Donna M. Recktenwalt         It’s a problem that many killikeepers encounter from time to time: badly skewed sex ratios in a batch of fry.         What causes these apparent shifts from the norm? And more importantly, what can we do about them?         Even the experts admit that there is much about fish embryology…

By Donna M. Recktenwalt        After extensive effort, you’ve finally succeeded in spawning and hatching out fry from that “special fish.” You’ve even successfully raised a number of them past the wriggler stage and into juveniles. You’re expecting the more or less normal sex ratio of 50/50.         But when they sex out you have…

 There has been considerable discussion in aquatic circles about the factors that may or may not influence gender determination in developing fry.         Now some evidence from the direct experience of at least one killikeeper has tested the link between water conditions and gender in killifish.         In September 1996, Gary Elson, writing on the…

By Donna M. Recktenwalt         Although the annual and semi-annual killifishesthe Nothobranchius of Africa and the Cynolebias of South America, as well as some of the Fundulopanchax species, and otherscontain some of the most beautiful and interesting members of the killifish kingdom, they are also among the most challenging to breed, given their substrate spawning behaviors and the need…

Thanks to Vitee Tao, via the Killifish (e-)Mail List         Here’s a new thick, chunky recipe for storing semi-annual eggs in this case, F. filamentosus (FIL).         Use a generous quantity of peat moss.         Add a small handful of java moss.         Introduce a pair or trio of FIL into a 12 inch tank (water also…

By Donna M. Recktenwalt                Variously known as green marl or Jersey Green Sand, greensand is a fine, altered dark-green sedimentary material (probably of oceanic origin, since shark’s teeth are sometimes found in it) that is mined and sold as a holistic fertilizer and soil conditioner for plants. It differs from silica sand by being…

  “One factor that may influence egg production is the moon,” observes Bruce Stallsmith. “Many fish … produce eggs in a cycle tightly linked to phases of the moon. Usually they breed best on a new moon, when nights are dark. Some North American killifish are known to do this, for instance, Fundulus heteroclitus, the mummichog, ……