You need to take the hippos back along with the scopas and the butterfly. Im sorry but it really comes down to that, If the store gives you any trouble call around to all the stores in the area and just ask if they will buy those four fish for store credit. There are a ton of possibilities as far as fish for your tank, unfortunately those four fish arent any of them. Those four fish wont survive in your tank, It may seem a little overboard for me to reccomend you removing all four of them but honestly it will be for the best. If you leave them they most likely wont live very long and your going to be out all the money and time you invested in them. I really suggest you at the least get store credit for them. I am including a link to liveaquaia.com If you go through the site you will run into a ton of information about a ton of different fish that you can comfortably put into your tank. I suggest using this site as your refference whenever your considering buying a paticular fish. Best of luck to you and your tank !
