Is there a disease in my fish tank?

When my oldest fish died,there started to be brown spots in my tank.Then one of my fish had a huge lump on its head!Then it died!Then one of my baby fish died!Then,one of my fish was bleeding.It had blood coming out of its gills!Then that one died!What do I do?
 
take the rest of the fish that are alive and put it in a different bowl for right now
 
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