Your fish tank is relatively alkaline, and the pH value of water generally does not exceed plus or minus 0.5. It is better to further balance the pH value of water. It is a famous saying that fish should be raised first. Alkaline, I guess you put a lot of stones. You'd better take off some, plant some aquatic plants, buy some cheap fish and wait a week to raise black gold. Although goldfish like alkaline water, it is not unlimited, and it is best to control it within 7.5.