CATDOLL : CATDOLL: How do Daphnia pulex appear naturally?

Either a cement pond or an earth pit can be used. Generally, the pond is 1m deep and 10-30m in area. Use bleaching powder or quicklime 10ppm to dry-clean the pond. After 7 days of exposure to the sun, add 0.5m deep water and then expose to the sun for another 7-15 days before applying fertilizer.

In cement ponds, 1.5kg/m3 of horse manure or other animal manure is added as basal fertilizer. In earthen ponds, the amount of fertilizer applied is 4kg/m3, with horse manure or other animal manure and 1.5kg of non-toxic plant stems and leaves such as straw as basal fertilizer. The purpose of basal fertilizer application is to promote the proliferation of algae in the water body.

The living habits of Daphnia:

Daphnia have a comb-like crown of green spikes on their heads that turn off predators. The crown of spikes is about 200 micrometers in diameter and appears in the offspring of Daphnia that can sense the chemical signals released by horseshoe crabs.

This fascinating image was created by exposing the fluorescence of some of the exoskeleton's internal tissues to the laser light of a microscope. This shows that lower organisms, even simple algae, can fluoresce.

For the above content, please refer to: Baidu Encyclopedia - Daphnia

1. Cultivation container: A water tank with a diameter of half a meter can be used, or a larger basin can be used. If there is a ready-made pond, it is also perfect. The water should not be too deep. Half a meter of water is considered deep, and the water quality is relatively turbid.

2. Light: Fish and insects have high requirements for light, so you can just put them in the sun. However, the sun is very strong, so if the water temperature is too high, you need to add cold water or put them in a cool place.

3. Feed: Fish worms mainly filter organic matter in the water, such as flour solution and milk. Don't feed too much, as long as there is enough water, they will not starve to death. However, if too much organic matter is added, the water quality will deteriorate.

4. Change the water: If the container has a large capacity, you don’t need to change the water. Just add water when the water evaporates too much. Don’t change too much water. You can seal the mouth of the straw with a stocking and then suck out some of the water.

5. Feeding: When there are a lot of fish worms, you need to take them out to feed the fish. Don't take too many fish worms at a time, otherwise the fish worms will grow slowly. Don't take more than two-thirds of the fish worms, just keep it at this amount.

6. Cleaning of fish worms: If you feed the fish directly with the fish worms, it may pollute the water in the fish tank. You can clean the fish worms first. The method is to put the fish worms in stockings and then rinse them with tap water.

Daphnia growth environment

1. Daphnia grow in stagnant water in rice fields or lotus fields. The leaves on the water block direct sunlight and prevent the water temperature from rising. The water is clarified through sedimentation and is suitable for the growth of Daphnia.

2. Sunlight can transform organic matter into food for Daphnia and purify the water quality. When there is a breeze, a film that isolates air and oxygen will not accumulate on the water surface, which helps Daphnia breathe.

3. Fish and worms like to live in slow-flowing fertile water, and the water depth is generally about 0.5 meters. Every year in late spring and early autumn, it is the season for large-scale reproduction of water fleas. Fish and worms float on the water surface, often making the water surface brown-red, which is easy for people to find.