From Facebook: The Killifish Lounge....
poor hatches of killifish eggs:
It has to do with where they're found and affects all the large west African killies and is so pronounced in A. kunzi, they're almost impossible to breed if attention is not paid. The problem isn't production of eggs, they can lay lots and lots, the problem is they're no good. But, in nature and in some peoples tanks (Ie. Rosario) they're all or mostly all good. The reason is the rare trace mineral Selenoum. Gularis, A. kunzi, and others are only found where this mineral occurs. Distribution of selenium in Africa is spotty and in North America even less abundant.
Bloodworms are the only fish food that contain any but the catch is they have to be harvested from an area fish in selenoum. So, try those, six weeks od bloodworms daily may solve the problem. If not try Wattley's paste food modified with selenium pills. (below)
Any decent veterinarian medicine book will have the phrase "nearly all reproductive failures are from too little selenium" (although too much can also be a problem in some areas where selenium is high - in the US this is parts of Utah) but when this happens other symptoms come first, ie, White Muscle Disease in mammals)
Frozen raw Beef heart, salmon and krill used by US discus breeder Jack Wattley. Modified by the author to increase mineral and selenium levels.
1 beef heart 2.5 pounds+, with fat
2 pounds Of fresh Salmon
10 ounces of Spinach
8 cloves of Garlic
6 ounces of Krill Meal
6 Multi-vitamin pills
6 Multi-mineral pills
6 200 mcg selenium pills (Selenomethione or Selenocysteine, not Sodium Selenite)
Soak vitamin and mineral pills in enough water to cover them or grind in a mortar.
De-fat the heart, grind in a grinder.
Grind the salmon.
Transfer to food processor, add krill, mix until a firm paste.
Put into freezer bags, flat.
Break a piece off when frozen and put it in the tank.
Does not keep in the fridge, use frozen.