Fish attacked in aquarium?

move the shark to a new tank. it can be kept in a 10g for a little while while you set up a 50g+ (thats the size they need). silver dollars should be in 3+ schools, tetras need 6+. they will be much more active and happy in groups. the molly should be fine. my angel had her feeler bitten off by another fish in the tank and it grew back completely within a month. all livebearers are good, especially guppies and platies. a school of cardinal tetras will brighten it up, so will a gold altum angel (if the tank is tall). neon blue dwarf gouramis are small and colorful, so are honey dwarf gouramis. a school of bronze cories can help clean up, they have an nice color. if the tank is long, a school of rainbowfish would be good.