Fish being bullied

[spideynat]

I used to have four fish, but sadly two passed away so i’m only left with the two. I never noticed this issue before but one of my fish has been bullying the other and I never noticed this issue when I had four (2 of each breed- I think 2 White cloud mountain minnows and i’m not sure of the other breed). What shall I do?

 

[Innesfan]

What size is your tank? It is difficult to offer advice without knowing what species we're talking about. Can you post a photo? Which species is being bullied and which species were the ones that died?