No, hamsters should not be fed fish.

Can hamster eat Fish

Hamsters are herbivores and their digestive systems are not designed to process meat or fish. Their natural diet consists of plant-based foods such as grains, vegetables, and fruits.

Feeding fish to a hamster can lead to digestive issues and potential health problems. Fish may contain high levels of fat, mercury, and other substances that can be harmful to hamsters. Additionally, the bones and small bones in fish can pose a choking hazard or cause injuries to the hamster’s digestive tract.

Also explore the compatibility of these foods for your hamster:
Pasta, Turkey, Beef,

It’s important to provide a balanced diet that meets the specific nutritional needs of hamsters. This includes providing a high-quality hamster food that is specially formulated for their dietary requirements. If you have concerns about your hamster’s diet or want to offer them additional treats, it’s best to consult with a veterinarian who can provide specific guidance based on your hamster’s individual needs.

Further Reading : 

https://vethelpdirect.com/vetblog/2023/05/20/what-is-the-best-food-for-hamsters/

https://www.ukpetfood.org/information-centre/pet-nutrition-hub/small-mammal-nutrition/hamster-nutrition.html