Water exchange: use a hose to suck the stolen goods in the water together with the water according to the siphon principle, and then replenish the water with the same quality or as close as possible. Generally, one third or half of the old water is replaced. Do not use "full water change" unless necessary; You can also install electric filtering equipment in the fish tank and connect it to the power supply, which can work automatically to filter out large particles and impurities in the water, and you need to clean the filtering materials in time.
Biological method: bedding sand (marble, black crystal sand, river sand or fairy soil, etc.). ) put it in a fish tank, and then plant a certain amount of aquatic plants. When the stocking density of fish is not very high, bottom sand and aquatic plants can precipitate and adsorb fish excrement, beneficial bacteria in the water environment can decompose fish excrement, and aquatic plants can re-absorb and utilize the decomposition products of beneficial bacteria. If the stocking density of fish tanks is high, physical filtration can be combined.
Sponge filtration, sponge provides habitat for beneficial bacteria and decomposes organic matter in water with a small amount of physical adsorption filtration, which is suitable for quiet fish and low-density feeding.
Fish culture method:
If you don't have the conditions to keep the water temperature in the fish tank, you should always give the goldfish plenty of sunshine in this cold winter.
Put some rice grains and some aquatic plants in the fish tank, but remember that the aquatic plants must be in moderation.
When feeding, you can throw some fish worms or white-flour steamed bread, but you should feed less and more each time.
Precautions:
When the weather is sunny, the warm wind is mild, the dissolved oxygen in the water is sufficient, and the water temperature is suitable, you can throw more bait appropriately.
When the water quality is thin and the fish has a big appetite, you can throw more bait.
If the fish is sick or the species is delicate, throw less coarse bait and throw some fine bait instead.
In order to distinguish the saturated digestion and absorption of goldfish, it can be distinguished according to the color of fish manure. Green, brown or black fish droppings indicate that fish are suitable for feeding and well absorbed. If the fish manure is white, it means that the fish is full.
Fish with large activity and strong vitality can eat more. On the contrary, less investment; It can be determined by trying to vote, and the first time you vote less. If the goldfish has finished eating in half an hour and is still looking for food, it means that it is fed too little, and it can be increased the next day.