Keep A Diary
Write down everything that has to do with breeding and progress of your ranchu. Documenting when and what is a good practice and creates an important database for your future reference.
Water Temperature During Hatching
68 F (20°C) is optimal water temperature for developing fertilized eggs. If the temperature is lover, fry will not hatch all at the same time and there will be a high percentage of malformed fish. Temperatures above 68 F (20°C) will induce egg development, resulting in higher percentage of tail regression to original "wild" carp. Controlling water temperature by shading and/or using a heater is necessary.
Water temperature and timing from spawning till hatching:
The fry are born with a yolk sac that provides them with nutrients for a couple of days. Start feeding the fry on the 2nd day after hatching.
Its best not to transfer very young fry during the water change, but scoop as much water as you can and replace it with fresh. When fry has grown a little it will handle the transfer better, still be very carful scooping it during the water change, to prevent any injury. At this time it is best to have two containers and alternate them during the water change.
Due to higher stocking density and/or food left in the water, filamentous green algae or Spirogyra can grow very rapidly. This algae produces long hair-like strings and if eaten by fry will get stuck in their small bodies, coming out through the gills or vent. It can not be removed and will eventually kill the fry.
Adjusting stocking density, regular water changes and cleaning the container will keep it under control.
Learn to determine proper stocking density. This will insure that the fry doesn’t die and will promote faster development. Balancing the amount of food and stocking density is important for a healthy development of the fry and to prevent a number of diseases.
It is important to make fry growing as fast as possible. For example, for the fish hatched in April, a goal would be to have the fish reaching 4 in (10 cm) in length by the fall.
Always pay attention to stocking density for the fry in its first year. High density will cause illness in fish and delays in development. During this period you want for the fish to grow lengthwise and loosen stiffness in their tails. Do regular water changes before water spoils. Regularly remove waist and uneaten food.
High Density:
movement is restricted, high probability of gill disease, growth is slow, rapid water quality deterioration, tail shoulders and core remain hard and make it difficult to swim
- 57 F (14°C) - hatching on the 7th day
- 61 F (16°C) - hatching on the 6th day
- 64 F (18°C) - hatching in 5 ½ days
- 68 F (20°C) - hatching on the 5th day
- 71 F (22°C) - hatching in 4 ½ days
- 75 F (24°C) - hatching on the 4th day
Feeding The Fry
The fry are born with a yolk sac that provides them with nutrients for a couple of days. Start feeding the fry on the 2nd day after hatching.
It is very important to provide enough food for the fry to keep up with their high growth rate. When feeding live food, the portion size is not important. The fry must eat as much as they need and any time they want. Digestion time is short. There should be a constant supply of live food, as it gets eaten from morning till evening. One of the most accessible live foods for fry is freshly hatched brine shrimp. Read more on brine shrimp here.
When feeding frozen food or micro pallets, the portion size need to be observed, as overfeeding can spoil the water fast. A single dose should be of what fry can eat in 5 min. Digestion time is longer. Intervals between feedings must reflect digestion times, but feeding must be preformed often.
It is very important to keep constant temperature during the water changes. Even small temperate fluctuations may weaken or kill very sensitive at this stage fry. Also, watch the aeration. Strong aeration can damage the fry, adequately adjust air pump pressure to minimize any water turbulence.
When feeding frozen food or micro pallets, the portion size need to be observed, as overfeeding can spoil the water fast. A single dose should be of what fry can eat in 5 min. Digestion time is longer. Intervals between feedings must reflect digestion times, but feeding must be preformed often.
Water Changes & Fry
It is very important to keep constant temperature during the water changes. Even small temperate fluctuations may weaken or kill very sensitive at this stage fry. Also, watch the aeration. Strong aeration can damage the fry, adequately adjust air pump pressure to minimize any water turbulence.
Its best not to transfer very young fry during the water change, but scoop as much water as you can and replace it with fresh. When fry has grown a little it will handle the transfer better, still be very carful scooping it during the water change, to prevent any injury. At this time it is best to have two containers and alternate them during the water change.
Filamentous Green Algae & Fry
Due to higher stocking density and/or food left in the water, filamentous green algae or Spirogyra can grow very rapidly. This algae produces long hair-like strings and if eaten by fry will get stuck in their small bodies, coming out through the gills or vent. It can not be removed and will eventually kill the fry.
Adjusting stocking density, regular water changes and cleaning the container will keep it under control.
Growth Rate
Learn to determine proper stocking density. This will insure that the fry doesn’t die and will promote faster development. Balancing the amount of food and stocking density is important for a healthy development of the fry and to prevent a number of diseases.
It is important to make fry growing as fast as possible. For example, for the fish hatched in April, a goal would be to have the fish reaching 4 in (10 cm) in length by the fall.
Growth rate of the fry indicating its healthy development:
- 1st week - 3/8 in (10mm)
- 2nd week - 1/2 in (13 mm)
- 3rd week - 5/8 in (16 mm)
- 1st month - 6/8 in (20 mm)
- 7/8 in (22 mm) increase in the 2nd month - 1 5/8 in (42 mm)
- 1/2 in (13 mm) increase in the 3rd month - 2 1/8 in (55 mm)
- 5/8 in (15 mm) increase in the 4th month - 2 6/8 in (70 mm)
- 5/8 in (15 mm) increase in the 5th month - 3 3/8 in (85 mm)
- 1/2 in (12 mm) increase in the 6th month - 3 2/8 in (97 mm)
- 5/16 in (8 mm) increase in the 7th month - 4 1/8 in (105 mm)
- food amount
- water changes
- adjust stocking density
Effect of Stocking Density On Tosai Ranchu
Always pay attention to stocking density for the fry in its first year. High density will cause illness in fish and delays in development. During this period you want for the fish to grow lengthwise and loosen stiffness in their tails. Do regular water changes before water spoils. Regularly remove waist and uneaten food.
High Density:
movement is restricted, high probability of gill disease, growth is slow, rapid water quality deterioration, tail shoulders and core remain hard and make it difficult to swim
Somewhat Low Density:
water quality is maintained, chances of illness are low, growth is higher in width and normal in length, competitive spirit and appetite is good, only tail core softens.
Low Density:
water may deteriorate causing illness even though it looks clean, growth in length is much suppressed, vertical growth is slower. Due to lack of competition between the ranchu, their appetite is lower, they swim less and because of that both tail shoulders and core remains stiff
Appropriate Density:
water quality is maintained, chances of illness are low, growth is higher in width and normal in length, competitive spirit and appetite is good, only tail core softens.
Low Density:
water may deteriorate causing illness even though it looks clean, growth in length is much suppressed, vertical growth is slower. Due to lack of competition between the ranchu, their appetite is lower, they swim less and because of that both tail shoulders and core remains stiff
Appropriate Density:
water quality is maintained, growth is accelerated in both length and width, better appetite and good competitive spirit, swims more. Both tail shoulders and core softening which helps to swim better. Adjust stocking density by culling. It is important to identify quality ranchu as early as possible to maintain appropriate stocking density.
Appropriate ranchu count per 3.3 ft² (1 m²) container that is 4 in (10 cm) gradually increasing to 10 in (25 cm) deep:
- up to 0.6 in (1.5 cm) long fish - up to 100
- 0.8 in (2 cm) long fish - up to 60
- 1 1/8 in (3 cm) long fish - up to 50
- 1 5/8 in (4 cm) long fish - up to 40
- 2 3/8 in (6 cm) long fish - up to 20
- 4 in (10 cm) long fish - up to 5
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Links to published chapters:
● INTRODUCTION
● WATER
● NOTES ON GREEN WATER & WATER CHANGE
● WATER TEMPERATURE
● AERATION
● SUNLIGHT AND SHADE
● CONTAINERS FOR RAISING RANCHU
● FOOD
● FEEDING REGIMENT
● BREEDING & SPAWNING
● RAISING & GROOMING FRY
● GROOMING KUROKO AND TOSAI
● CULLING
● SELECTION METHODS
● CULLING ROUND - I
● CULLING ROUND - II
● CULLING ROUND - III
● CULLING ROUND - IV
● CULLING ROUND - V
● FORSEEING RANCHU CHANGES IN THE FUTURE
_________________________________________________________________________________
Links to published chapters:
● INTRODUCTION● WATER
● NOTES ON GREEN WATER & WATER CHANGE
● WATER TEMPERATURE
● AERATION
● SUNLIGHT AND SHADE
● CONTAINERS FOR RAISING RANCHU
● FOOD
● FEEDING REGIMENT
● BREEDING & SPAWNING
● RAISING & GROOMING FRY
● GROOMING KUROKO AND TOSAI
● CULLING
● SELECTION METHODS
● CULLING ROUND - I
● CULLING ROUND - II
● CULLING ROUND - III
● CULLING ROUND - IV
● CULLING ROUND - V
● FORSEEING RANCHU CHANGES IN THE FUTURE
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