Koi fish is a type of ornamental fish which means “carp”, is a selective breeding variation of carp (Cyprinus carpio) brought to Indonesia by the Emperor of Japan during a state visit in 1991. This fish is widely bred because it has beauty and uniqueness. It is explained that the cultivation and spawning of koi fish can be done easily if you follow the correct procedures.
Spawning is one of the processes of releasing female eggs and male sperm which will then be mated with the aim of getting the desired fish seeds. Koi fish are one of the fish that can be spawned with human assistance considering the relatively expensive price of koi fish because spawning is very much needed to produce superior seeds.
Spawning Media
Before carrying out the spawning process, prepare the spawning pool first. The spawning pool is made separately between the male and female parents. Requirements for a koi fish spawning place that you can practice:
- Try to make the spawning pool made of cement and make sure the surface is smooth to keep the fish scales from being damaged and injured during the spawning process.
- The size of the pool varies depending on the location and environment around the pool. Some koi hobbyists use a pool size of 3 x 6 meters with a depth of 60 cm and a height of 40 cm.
- Make sure the pool has good water circulation in and out because it is known to be quite effective in stimulating koi fish to fertilize with continuous flowing water conditions, there is a fine filter to prevent pests from entering and disturbing the larvae and preventing larvae from drifting out of the pool.
- The pool must be dried and dried in the sun which aims to kill disease agents from bacteria, fungi, viruses or other agents that can be transmitted to fish.
- In addition, the water to be used should be settled first for approximately 24 hours. This aims to precipitate inorganic materials that can poison or interfere with the spawning process of koi fish.
Koi Fish Spawning Process
After knowing some things that guarantee the right spawning place for koi fish. also need to pay attention to the stages of koi fish spawning, namely as follows:
- In the spawning process, make sure the kalam is ready to be entered by the parent fish.
- The sign that the fish will start spawning begins with the female parent swimming around the pond followed by the male and trying to attach its body to the female.
- The movement around the pond will get faster until the female fish releases her eggs which will stick to the kakaban and the male fish releases sperm and fertilization occurs.
- The spawning process at night – morning, therefore it is better to insert the parent fish in the afternoon so that spawning occurs as soon as possible.
- In addition to natural spawning, it can also be done with human assistance with hormone stimulation on the female parent to speed up the fertilization process. Injection of ovaprim dose 0.2 mg / kg fish weight for one injection.
- Ovulation occurs 10 hours after injection. After spawning is complete, immediately remove the parent fish from the spawning pool because if left alone, it is feared that the male parent fish will eat all the eggs.
Hatching Koi Fish Larvae
The next stage in the hatching process of koi fish larvae requires the following stages:
- It should be done in a pond or place specifically for hatching so that it hatches properly. Eggs attached to the kakaban must be submerged in water.
- If the water temperature is cold, the hatching time will be longer and vice versa if the temperature is too hot the eggs will rot.
- Newly hatched fish larvae still store leftover food in themselves which is obtained from the egg yolk when it was still an egg.
- The feed that can be given is egg yolk that is ground and mixed with water.
- Dirty pond water can cause death to larvae. As a substitute, filtered water fleas (daphnia) can be given. This feed is given until the fry are 1 cm in size.
Koi Fish Nursery
For the koi fish nursery stages in koi fish cultivation, there are two, namely:
- Nursery I is carried out for 2 months of maintenance from larvae – fingerling/finger size (2 – 3 cm).
- Nursery II is carried out to grow natural food, carry out selection and thinning.There are several important requirements for the koi fish nursery process that you need to pay attention to as follows:
- To reach fingerling size it takes 6 – 8 weeks, a size of 5 – 8 cm takes 4 months.
- To carry out nursery must be in a special pond for nursery usually keep koi until the age of 3 months.
- The size of the nursery pond is usually 3 x 4 with a depth of 40 cm can accommodate 250 – 300 fry.
- At this age the fish can be given pellet feed with a size of 250 microns in a day given 2 times.