Reasons for parrot fish rubbing against the tank:

1. Parasitic infection. Due to unclean food and lack of disinfection measures for new fish entering the tank, parasites or eggs enter the fish tank and then invade the fish body, causing the fish to rub against the tank.

2. Caused by fright. Parrot fish may also rub against the tank after being stimulated or disturbed by the outside world.

3. Changes in water quality. If the water quality of the fish tank where the parrot fish lives changes greatly, such as rapid temperature changes, rapid changes in pH value, large amounts of new water injection, large pollution of the water in the tank, etc., the parrot fish may rub against the tank.

4. Caused by estrus. During the estrus period, especially when the female parrot fish is laying eggs, the temperament will be more irritable.

5. Play and play. Sometimes it is normal for fish to occasionally rub against the tank while playing in the water, but if it rubs against the tank frequently, there is a "problem".