Can fish and persimmons be eaten together?
Generally speaking, it is not recommended to eat fish and persimmons together. The detailed explanation is as follows:

Fish is rich in protein, calcium, and other minerals. Persimmons, especially unripe ones, contain a certain amount of tannic acid. When this tannic acid interacts with the protein and calcium ions in fish, it may form indigestible precipitates. The formation of such precipitates could interfere with the digestion and absorption of fish, potentially causing discomfort symptoms such as abdominal distension and pain.
Moreover, both fish and persimmons are considered cold-natured foods. Consuming them together may increase the burden on the gastrointestinal tract. Individuals with weak spleen and stomach function are particularly prone to digestive issues such as indigestion and diarrhea when consuming fish and persimmons together.
If one's physical condition and health status permit and the amount consumed is moderate, it may be acceptable to wait several hours after eating fish before consuming persimmons, in order to reduce interactions between food components. Individuals with weak spleen and stomach function or poor digestion should consume fish and persimmons cautiously to avoid increasing the gastrointestinal burden or causing discomfort.