Ranchu eggs and fry
Eggs are 1 mm amber beads; fry are slivers with eyes. Here is what to expect each week and what to feed.
What the eggs look like
Ranchu eggs are about 1 mm across, sticky, and scattered over mops or plants in clumps. Fertile eggs are translucent amber, and after a day you can see two dark specks (the eyes) inside. Infertile eggs turn opaque white within 24 hours and grow fungus; pick them out or they will infect neighbours. A few percent white is normal; mostly white means the males were not ready or the water was too cold.
Week by week
- Days 0 to 4: Eggs. Keep 70 to 75 °F, gentle air, no filter intake that can suck them up. Hatching on day 3 to 5.
- Days 4 to 7: Fry hang on glass and mops, absorbing yolk. Do not feed.
- Week 1 to 3: Free-swimming. Feed newly hatched brine shrimp 3 to 5 times a day. Bellies should look orange after each feed. Small water changes daily with aged water.
- Week 3 to 6: Tail shape becomes visible. First cull: remove single-tailed and deformed fry. Add crushed pellet or fry powder alongside brine shrimp.
- Week 6 to 12: Body deepens, dorsal-less back is obvious. Second cull for dorsal spikes and bent backs. Move to larger, shallow tubs and thin the numbers; crowding stunts them.
- Month 3 onward: Colour change begins: fry are bronze and turn orange, white or red-and-white over weeks. Feed like tosai: sinking pellet plus frozen food. Wen begins to show at about four months in heavy-wen lines.
Common losses
Most fry die from one of three things: overfeeding that fouls the water, an ammonia spike from a tub with no established bacteria, or being sucked into a filter. A sponge filter seeded from an adult tank solves two of the three. Feed little and often rather than a lot at once.
The full process from conditioning to culling is on the breeding page.