Observe the health of fish. Healthy fish are bright in color, intact, lively and have a strong appetite. The sick fish is slow-moving, disabled or damaged, and refuses to eat.
Individual differences of ornamental fish are more common. Often the body is bent, the fins are asymmetrical and uneven, and the mouth and eyes are weird. Although in good health, there are congenital defects that affect the appearance.
C try to choose water-fixed fish species, which often adapt to local water quality and have high survival rate.
Choose the best fish in large quantities. First, there is a lot of choice. Second, the price is cheap. Third, it is not easy to buy residual fish to kill fish.
Generally, plastic bags filled with oxygen are used to carry and transport. Be careful not to expose the air and not to bump violently. In rainy and low-pressure weather, high temperature in summer and low temperature in winter, arowana is not suitable for transportation and carrying. Choosing sunny weather to buy fish can reduce losses. Some large arowana can be transported by anesthesia to slow down their metabolism.
The water temperature and quality in the plastic bag brought from outside are different from those in the tank at home. If the fish is directly put into the tank, the water temperature and quality will suddenly change, which will make the exhausted fish worse and easily lead to its death. Water treatment, the specific operation method is:
A Don't open the plastic bag, put it in the jar and let it float on the water of the fish tank, usually 10-30 minutes. If the temperature difference is too large, the time can be appropriately extended to make the water temperature in the cylinder consistent with that in the plastic bag;
B Open the plastic bag, pour out some water, then pour some water into the jar, tie the bag tightly and let it stand for 5 minutes;
C take out the fish with a fishing net and put it in a fish tank. Empty all the water out of the bag. Don't pour into the fish tank.
After putting the fish in the fish tank, don't feed it for a few days. When it adapts to the water quality and environment, don't hit the fish tank to scare it. The principle of polyculture is to give priority to parrot fish, and a small amount of fish can also be added.
After the filtration system runs for a period of time, a lot of dirt will accumulate in the filter material, which will reduce the filtration effect. At this time, it is necessary to clean and replace the filter material. When cleaning, turn off the power supply, clean the filter cotton in the physical filtering part with clear water, and replace some filter cotton. Biofilter materials such as ceramic rings and biochemical cotton can be cleaned for a longer time and replaced gradually. Most of the filter materials must not be replaced, otherwise a large number of nitrifying bacteria will be lost, and the filtration effect will be greatly reduced. Secondly, do not use any chemical cleaner, hot water or cold water to clean the filter material. It is best to take out part of the water in the tank and clean it to ensure the survival of nitrifying bacteria. In addition, the inlet and outlet pipes should be cleaned to prevent blockage, electrified after installation, and checked for water leakage.