1. Cause: Feeding fish in hard water will make the fish black. When the acidity and alkalinity of water change too much, the fish will not be able to adapt to the new water quality conditions, resulting in black fish.
2. The treatment method is as follows: the PH of the water is adjusted to be between 5.5 and 7. When the water quality is hard, a resin for softening the water quality can be added to reduce the hardness of the water. In order to avoid the sudden change of water quality, the new water used in water exchange should keep the same PH and hardness as the old water.
1. Cause: a sudden rise or drop in water temperature will cause the fish to produce a stress response, so that its body loses luster, body color is dim, and even appear black stripes or local blackening.
2. The treatment method is that the water temperature is kept between 25 deg C and 28 deg C in the feeding process, and the temperature is kept stable. Every time water is changed, the temperature difference between new water and old water should not exceed 0.5 C. In winter, use the heating rod to increase the temperature of the fish tank to avoid the temperature drop.
1. Reason: If the daily care is not in place, resulting in fish injuries, there is no timely treatment of wounds. The mold in the water may parasitize the wound of the fish and infect the fish with black spot disease.
2. Treatment: First use of salt water and sodium bicarbonate mixed solution to sterilize the fish tank. And then new wat is poured in, malachite green or methylene blue is dissolve in that water, and the fish is put in the water for immersing and was for 10 to 20 minutes. Once a day, after a period of time, the mycelium of the mold will slowly fall off, and the black on the fish will gradually disappear.
