Here is the deal. Clown loaches and loaches in general like to be in a group or they can get aggressive with other fish. In addition clown loaches get huge, over 12 inches and unless you have a real big tank, they will be inappropriate. I don't know why they are so popular as they don't work in many tanks. I would rehome or if you have a 100 gallon tank or bigger, get a few more.
Make certain you research every fish you buy and don't depend on the fish stores to be informed.