New tanks often go through a period where they cloud up, just do a water change making sure the water you put in is as warm as the tank water. It should clear after a day or two. In terms of the Sharks by the heater, have you checked the tank temperature? Could be too cold, otherwise if you don't have any hiding places it could be that the new fish are crowding around the heater for cover.
The fish that you have are unsuitable for the tank so at some point fairly soon I would recommend trading them all and stocking appropriately with small fish, Barbs, Tetras or danios, Dwarf Cichlids, small Gouramis, corydoras etc. You basically have a wide choice.
