Whats up with mirrors and betta help please?

Answers

Book Shelf

Bettas will attack their reflection, perceiving it as a threat to their territory. It's interesting to see every now and again, but don't leave a mirror in or near the tank. If it can constantly see its reflection it can get stressed and sick. But every once and a while is fine and mentally stimulating.

Toruko

Fish are interested in flashy prey. Mirrored surfaces using metal are common. Every so often we see a new shiny thang touted as better. Hooking customers.