The important thing for Medaka is "light". Medaka lives originally in the sunny waters. Even when rearing, "light" is a very important element.
Sunlight is an important factor for Medaka. The yokihi-based medaka is redder by being exposed to sunlight. In addition, the survival rate of juvenile killifish is higher if they are exposed to sunlight. It is probably due to the fact that sunlight kills the bacteria that cause the disease.
However, if exposed to sunlight for a long time, the water temperature rises too much and kills the medaka. It is recommended to float the water plants and to shade the half of the breeding container with a board. Water plants not only make shadows but also hideouts, become place to lay eggs and become pumps that provide oxygen into the water. It also plays a role in water purification.
When rearing indoors using a glass aquarium, placing the aquarium in direct sunlight can cause moss and algae, so it is better to avoid direct sunlight when viewing indoors. It is recommended that you raise juveniles in a place exposed to sunlight, and when it is about 1cm, move them to a water tank in the room.
It is recommended that you use lighting instead of sunlight if you want to keep medaka in a glass aquarium indoors. It does not have the same effect as sunlight, but it grows aquatic plants and has a certain effect on darken the color of medaka.
Lighting equipment is essential to enjoy the aquarium. Lighting is required to maintain a clean aquatic aquarium. Recently, LED lights have become mainstream and running costs are low, so it is better to enjoy aquariums using aquatic plants and lighting equipment when rearing medaka indoors.
Aquarium corner we have established an "Aquarium with Medaka!"
Time zone to use lighting
Medaka has a 24-hour clock like the human body. And, like humans, it is adjusting the internal clock at sunrise and sunset times.
As the result, the indoor breeding Medaka can not adjust the body clock at sunrise and sunset times, and may become ill. It is recommended to use the lighting also for Medaka internal clock adjustment.
Also, the lighting hours are from sunrise to sunset. The bright and dark hours allow Medaka to adjust the body clock. By adjusting the time to sunrise and sunset, we can inform the medaka of the four seasons, and we can encourage egg laying.
If you want to spawn even in winter, adjust the time zone that uses the lighting to be the same as spring daylight hours. The temperature of the water can be adjusted even in winter by adjusting it to the temperature of spring.
Column -Lighting costs-
When it comes to lighting, it's a matter of equipment and electricity. In recent years, it has become common to use LEDs for lighting, and the running cost of lighting used for a 60cm aquarium is around tens of cents a month. However, LED lights are a little expensive, and if they are 60cm, they cost more than $40. In addition, the LED bulb cannot be replaced, so you have to buy a new one after one breaks.
But it is too early to see it as expensive. Sunlight causes algae to breed in the aquarium, which quickly turns green and requires frequent water changes. The water temperature changes greatly, and the water temperature rises too much, sometimes killing medaka. In addition, if you do not use lighting in a place that is not exposed to sunlight, the health of medaka cannot be maintained. It is easy to get sick, and the cost of treatment tends to be high.
You can also grow plants in the aquarium if you use lighting. Weeds purify water and also supply oxygen to the water. Weeds make the environment in the aquarium more comfortable and, as a result, reduce the frequency of water changes and cleaning, which has the effect of reducing costs.