What foods are forbidden in Santan Dharm?

Fish is not food.

There is food of 3 kinds. Satvik which is free from meat and this for any person who is highly devoted to God(Sri Bhagwan). The highest duty of a Hindu is to practice “ahinsa parmo dharm” which means to practice non-violence as the highest duty. The second kind of devotee is rajsik. This is the mode of passion so here you can have some food that is acidic, spicy, fried food etc… Then there is the tamsik. The demonic nature. The food group includes meat, poultry, fish, eggs, alcohol and other intoxicants including drugs. So clearly Hinduism is against meat eating but you can eat it but it falls into the demonic nature. Plus it is not good for the mind and leads to decline in spiritual practice.