Cage farming for fish is the most common culture. No doubt, it is one of the oldest culture forms. And lots of people make money with that.
Before deciding to put your investment into this field, do you know the differences between filter-feeding fishes and herbivorous fishes? Have you got any idea how to treat them culturing differently?
Because if you don’t, you are putting your investment into a big risky edge and may come into failure, which you apparently don’t want that happened.
In this article, we are going to show you the 3 most important factors regarding cage fish culture.
1. Filter feeding fishes culture
Currently, silver carp and bighead are the main species for cage culture. People use natural bait in the water to breed. It has the advantages of small investment and no pollution. Meanwhile, it has the features of good efficiency, good quality, and safety.
Silver carp and bighead are typical filter-feeding fishes. They grow fast. At the age of 2~3, their weights can be increased from 1 kg to 4 kg. The maximum can reach 40 kg. Natural production is very high. Here are the main technical bullet points:
Setup cages in the right place
Generally, people should select floating closed cage. The cage should be placed near the farmland. The water should be shallow, fresh and oxygen-rich. The flow rate should be 0.05 to 0.2 meters per second. If the rate is too high, it will consume fishes’ energy. It will be harmful to fishes’ growth.
Keep cages sparse
The cages cannot be too dense. Otherwise, it will make the food insufficient. In general, each cage should be kept at 5~20 meters from another. It can smooth water flow and increase the oxygen supply.
Clean cages frequently
For cage culture, the feeding mainly depends on the plankton in the water. Thus, it is very important to keep the water smooth and the net clean. That can keep a good water supply.
2. Herbivorous fishes culture
The main herbivorous fishes in cage culture are grass carp and bream. They have the advantage of high yield and profit. But the disadvantage is high disease risk. For grass carp, the time for length growth is the 1~2 year(s) old. The time for weight growth is 2~3 years old. After 5 years, they grow slowly. Here are the main technical bullet points:
Setup cages properly
Generally, the fixed & open cage is preferred. The cage size should be more than 60 square meters. The net should be at least 40 centimeters above the water. It can prevent the fish from jumping out.
Keep cages sparse
For herbivorous fish culture, a large number of feeding is required. Hence, the water exchange should be smooth. The cages should be scheduled in order. The distance between each column is about 15 meters. In each column, there are about 3.5 meters between each cage.
Feed fish scientifically
At present, most cage culture mainly depends on commercial bait. Some forage is supplemented as well. When feeding, the daily bait weight should be 3% to 5% of fish weight. Separate it into 3~4 times per day.
Manage cage daily
We should keep checking fish growth daily and write a fishery log. Find the damage net and repair in time. Prevent the fish from escaping and keep enemy fish away. In the flood season, we also need to check the ropes and nets. Clean the net cage every 10~15 days. Remove residual bait and algae attached. Keep the water well exchanged.
3. Carp cage culture
It’s been a long history for crucian carp cage culture. The technology for this culture is also very matured. Here are the main technical bullet points:
Choose the right net cage
The cage should be in a rectangular shape with polyethylene mesh. The measure is generally 20~30 meters square and 2~3 meters high. Mesh should be 3 centimeters, according to fingerling size.
Decide the feeding volume
Feeding depends on the weather, water temperature, and fish. If the water temperature is below 18-degree centigrade, the daily feeding weight should be 1% to 3% of fish weight. Separate it into 2 times per day. If the water temperature is above 18-degree centigrade, the daily feeding weight should be 3% to 5% of fish weight. Separate it into 3-5 times per day.
Manage cage daily
According to the water and mesh, people should clean the cage frequently. The dead fish and dirt should be removed from the cage in time. Monitor the fish every day. Sterilize frequently. It is usually 1 time per month.
Prevent & control disease
To avoid unnecessary fish injury, carefully operate the cage. People must sterilize the fish before putting into the cage. Disinfect the water Regularly. Find out and remove the dead fish. The fishing gear should be disinfected.