The amount of feed for angelfish varies depending on the age and size of the fish. For juvenile fish (with a body length less than 5 centimeters), they need to be fed 4 to 6 times a day, and it's advisable that the amount of each feeding allows the juvenile fish to finish eating within 2 to 3 minutes. For sub-adult fish (with a body length between 5 and 10 centimeters), they should be fed 3 to 4 times a day, and it's better that the amount of each feeding enables them to finish within 3 to 4 minutes. For adult angelfish (with a body length greater than 10 centimeters), they are fed 1 to 2 times a day, and it's optimal that the amount of each feeding makes them finish within 5 to 6 minutes.
The types of feed and the feeding schedule are also very important. Angelfish are suitable for eating pellet feed and cake-like feed. Among pellet feeds, the fine powder feed with small particles is the most favored by angelfish as it can float in the water for a long time and remain fresh. Cake-like feed has relatively comprehensive nutritional components and won't cause water pollution due to the breakage of bait. Feed them 2 to 3 times a day, and control the amount of each feeding to be about 5% of the fish's body volume. It's best to feed them in the morning.
Other factors that affect the amount of feeding include water temperature, water quality, etc. When the water temperature is between 28 and 30 degrees Celsius, angelfish have a better appetite and can be fed with the normal amount. If the water temperature is lower than 25 degrees Celsius or the water quality is poor, such as excessive ammonia nitrogen and nitrite content, it's necessary to reduce the amount of feeding or even temporarily stop feeding until the environmental conditions improve.