The three major taboos for changing water for blood parrot cichlids mainly include the following points:
Excessive water change at one time: The amount of water changed each time should not exceed one - third or one - fifth of the total water volume in the fish tank. If too much water is changed at once, it will cause a significant change in water quality. Blood parrot cichlids may not be able to adapt, which may lead to a stress response and even make them sick.

Large temperature difference: The temperature difference between the new water and the old water when changing water should not exceed 2°C. Blood parrot cichlids are very sensitive to water temperature changes. A large temperature difference may reduce their immunity and even make them ill. Therefore, before changing water, the temperature of the new water should be adjusted to be close to that of the water in the fish tank.
Using untreated water: Using tap water directly may lead to chlorine residue, which can harm blood parrot cichlids. Therefore, the new water must be left to stand and treated in advance to remove chlorine and ensure water quality safety.
Correct water - changing steps and precautions:
Preparation before water change: Stir the bottom sand to clean impurities and ensure the water quality is clean.
Control the amount of water change: Control the amount of water changed each time to be between one - third and one - fifth of the total water volume in the fish tank.
Adjust the water temperature: The new water should be pre - warmed in advance to ensure it is close to the water temperature in the fish tank, with a temperature difference not exceeding 2°C.
Treat the water quality: Use water that has been left to stand or water treatment agents to remove chlorine.
Change water slowly: Gently suck out some of the old water with a straw or container, and slowly pour in the new water along the wall of the fish tank to avoid directly impacting the fish.
Add beneficial bacteria: Add an appropriate amount of beneficial bacteria such as nitrifying bacteria during the water - changing process to improve the water quality environment.