most lfs people will say what the hell they feel might help sell a fish. seriously never trust them. clown loaches grow to big for the tank simple as discus are for expert fishkeepers only as they are tricky to keep healthy, angels and neons can work but it all depends, why bother to ask a question if when you receive an answer you simply disagree, if thats your attitude simply get what you want and enjoy wasteing your money and flushing the dead fis! i dont mean to be aggresive im just trying to get my point across to you.
now onto helping you angels would be fine in that tank just keep either 1 a male and female pair or a minimum of 6, instead of clown loaches perhaps khuli loaches or a corydoras of some sort of plec.