1, the fish tank is small, there are too many fish, or the power of the filter screen is low, which can't completely filter the dirt, and the green algae will grow rapidly. A large number of foreign bodies such as granular impurities and short fibers that fall off will cause water turbidity. However, this turbidity is not terrible, and most impurities can be filtered out in a few days.

2, feeding too much, the fish can't finish the feed, the feed rots in the water, and the water quality is over-nourished, so that substances such as ammonia accumulate quickly in the water. Nitrifying bacteria will be transformed into nitrate after nitrification, and nitrate is an important fertilizer for aquatic plants and algae. If the water contains a lot of nitrate, algae will grow wildly.

3. The quantity of fish and bait should be moderate, and the honey juice of fish is too big. Feeding too much bait is equal to increasing pollution. The water in the fish tank is polluted by fish droppings, food residues and rotten leaves of aquatic plants.

There are some inferior baits in the market. In order to increase the price, pigment was added. When feeding, the pigment in the bait will dissolve into the water and make the water discolor. If this happens, the bait should be replaced to solve the problem.

5、? Shortly after the water tank is set, when the water quality is unstable, when the light is insufficient, when the oxygen content in the water is too low, when the light is insufficient or weak, when the nitrate in the water is too much, such as reaching more than 50ppm and the pH value is too high, such as above 7.5.

Extended data:

Measures to solve the turbidity of fish tank water;

1, the most important thing is to have an effective ecological filtration system, including mechanical filtration and biological filtration. The usual mechanical filtration can only remove solid pollutants, but there are still a lot of organic substances dissolved in water, such as protein, which cannot be filtered out, and can only be completed by biological filtration system.

2. The water in the fish tank will be polluted by fish feces, food residues and rotten leaves of aquatic plants. In people's imagination, filtering out the visible suspended solids in the water and keeping the water clear and transparent will achieve the goal. In fact, this is only the primary function of filtration, which we usually call mechanical filtration.

3. The filtration of modern ornamental fish tanks should have both mechanical filtration and biological filtration, and sometimes physical filtration is needed. Among them, biological filtration is particularly important. The so-called biological filtration is to decompose or convert harmful substances dissolved in water into harmless substances through bacteria attached to filter materials, which is the most important filtration function. Physical filtration uses the unique adsorption function of some materials (such as activated carbon) to purify water. Physical filtration is only used for a short time under special circumstances, such as removing residual chemicals in water.

4. The filtering capacity of the filter should be large enough. The filtration capacity of the filter is expressed in liters/hour. When filtering water, it is generally required that the filtration volume should reach 3-5 filtration cycles. Specifically, if the water in the fish tank is 200 liters, it should be equipped with a filter of 300- 1000 liters/hour.

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