Is zebrafish a freshwater fish, or a saltwater fish? 5

Originally, it was a marine fish, but now it has been desalinated and cultivated. Feed creature bait and control the light.

Zebrafish, also known as blue-striped fish, flower striped fish, zebradanio rerio, is native to India and Bangladesh.

1. Features. Body length 4, 6 cm. The body is spindle-shaped.

The dorsal part is olive-colored, with several silvery-blue longitudinal stripes extending from the back of the operculum to the tail, and the anal fin also has longitudinal stripes similar to the body color, and the caudal fin is long and forked. males lemon-colored longitudinal stripes; The female has blue longitudinal stripes with silver-gray longitudinal stripes.

2. Feeding and ornamentation.

Gentle and delicate, he swims in the aquarium almost all day long. Easy to raise, can be mixed with other species of fish. Feeding water temperature 20 23, in the water temperature 11 15 can still survive, the water quality requirements are not high.

For daily feeding, put some pebbles at the bottom of the aquarium to make the water clear.

3. Scientific utilization.

Because the gene similarity between zebrafish and human genes reaches 87, which means that the results obtained from drug experiments on zebrafish are also applicable to humans in most cases, it is valued by biologists. Because zebrafish embryos are transparent, biologists can easily observe the effects of the drug on the organs in their body. In addition, female zebrafish can lay 200 eggs, and the embryos can develop and form within 24 hours, which allows biologists to conduct different experiments on the same generation of fish to study the pathological evolution process and find **.

4. Reproduction. It is not difficult to distinguish between male and female zebrafish: male zebrafish have a slender body, large fins, yellowish body color, brownish-yellow anal fins, and prominent stripes; The female fish has a fatter body, a lighter body color, a bluish tinge, a pale yellow anal fin, and an obvious abdominal expansion during the egg-bearing stage.

Zebrafish is an oviparous fish that enters sexual maturity at the age of 4 months, and generally reproduces well with 5-month-old fish. Water requirements for reproduction, hardness 6-8, water temperature 25-26 degrees Celsius. Like to spawn at the bottom of the aquarium, zebrafish like to eat their eggs the most, generally choose 6-month-old broodstock, in the 25 cm x 25 cm x 25 cm square tank bottom lay a layer of nylon net board, or lay some pebbles, after breeding will fall under the net board or scattered in the gap of small pebbles.

Select 2 or 3 pairs of broodstock, put them in the breeding tank at the same time, and generally take out the broodstock from dawn to about 10 a.m. the next day. The eggs are non-sticky and fall directly to the bottom of the tank, and at about 10 p.m., the eggs that have not been fertilized are white and can be sucked out with a straw. At the breeding water temperature of 24, the fertilized eggs hatch larvae after 2 to 3 days; At a water temperature of 28, the fertilized eggs hatch after 36 hours.

Females lay more than 300 eggs at a time, up to 1,000 eggs. When the water temperature is 25, the larvae of 7 to 8 days are fed, and the egg yolk gray water is fed at this time, and the small fish and insects are fed later. The breeding cycle of zebrafish is about 7 days, and it can reproduce continuously 6-7 times a year, and the spawning is high.

It is highly fertile, making it the preferred breed for beginners in tropical fish.

Groupers are freshwater fish. The grouper is not a marine fish, but a freshwater fish with a high nutritional value. Moreover, the economic value of the precious grouper is very high, its meat is delicious, it sells well at home and abroad, the price is expensive, and it is one of the important aquatic products exported by our country.

Grouper is rich in nutrition, the meat is delicate and white, similar to chicken, known as "sea chicken". Grouper.

It is also a kind of low-fat, high-protein high-grade edible fish, which is promoted by Hong Kong and Macao as one of the famous fish of China's four eggplant, and is a must-have delicacy for high-end feasts.

Eating habits:

Groupers are ferocious carnivorous and voracious. The predator varies with the size of the fish. The main food of seedlings with a body length of less than 3 cm is the larvae of scratch pods, cladopods and midges, etc., and the seedlings with a body length of less than 3-8 cm feed on the larvae of aquatic insects, tadpoles, small shrimps, larvae, etc.

Grouper is a freshwater fish.

Grouper fish generally live in lakes or streams, and are also a type of carnivorous fish, often other fish or crustaceans.

Organisms feed on. In addition, the grouper fish is very territorial, and if it is invaded by other fish, the grouper will launch a fierce attack on it. Of course the beautiful appearance of the grouper fish assumes it an ornamental fish.

It is also a good choice, but due to its ferocious habits, it is not suitable for polyculture with other fish.

The grouper fish is very similar in appearance to the black fish, its body color is silver-blue-gray, the belly is white, the mouth is relatively large, the chin is slightly protruding, the whole body is covered with irregular spots, and there are some black stripes around the eyes and gills. The physical characteristics of the grouper fish are very obvious, and friends can easily distinguish it when they see this fish.

Cultivation methods

1. Breeding pond conditions: The pond can be dug in the low and middle tide areas of the reclamation area to build a pond or build a shrimp breeding pond by using the original shrimp breeding pond. The conditions are:

The substrate is better to be sandy or semi-sandy, and hard mud bottom is also acceptable; The water quality of the surrounding sea area is pollution-free and transparent; The fish pond area is 5-10 acres, and the water depth of the pond is more than 1 meter.

2. After the fish pond is exposed to the sun and dredging, lay some rocks or put some perforated waste tires and tile water cylinders at the bottom of the pond to adapt to the habit of grouper fish like to drill holes.

Groupers are saltwater fish.

Groupers prefer to inhabit the rocky reefs, gravel, and coral reef bottoms near the coastal islands, and generally do not form groups. The inhabited water layer rises and falls with the change of water temperature. It is distributed at a water depth of 10 30 m in spring and summer, and also occurs at a water depth of 2 3 m in midsummer. In autumn and winter, when the water temperature drops, it swims to a depth of 40 to 80 meters.

The optimal temperature range is 15 34 , and the optimal water temperature is 22 28. It has a wide range of suitable salinity and can survive in sea areas with salinity above 10. It is a carnivorous and ferocious fish that preys on benthic crustaceans, various small fishes and cephalopods in a raiding manner.

Cichlidae is a genus of melanochromis fish.

The figure below is shownMelanochromis auratus, popularly known as the African Phoenix.

<> has a black stripe on the dorsal fin. Adult females retain this body color, while males turn dark blue-black, with a metallic shallow grip or blue stripe on the side of the body from the posterior edge of the gills to the end of the caudal peduncle. This fish has a strong sense of territory.

Juvenile fish can be polycultured, and males often fight, so polyculture requires a larger aquarium and more aquatic weeds, rocks and other hidden places for vulnerable fish to hide. Adults should be kept alone.

Traditional red and blue zebras.

In recent years, many excellent zebrafish species have been artificially improved. Compared with the traditional red and blue zebras, the current breed has a variety of fluorescent colors, candy colors, etc., so that aquarium fish players have more choices. Number of cracks.

Red-orange zebra. The red-orange zebra exudes a sweet orange color, which is bright and can return to love, making people reluctant to leave for a long time.

Difference 1, different body types.

The male fish are slender in size.

The body of the female is obese.

Difference 2, the color is different.

The males are slightly darker in color.

Females are slightly lighter in color.

Difference 3: The state of the stripes is different.

The males have distinct stripes of lemon-colored stripes between dark blue stripes.

The female is slightly lighter in color, with blue stripes and silver-gray stripes.

Difference 4: Different performance after sexual maturity.

After the female reaches sexual maturity, the abdomen will become fattened and buryed. Males don't.