You need to remember the universal rule no mater what is that big fish eat small fish. You would be surprised at how big some fish can open their mouths and I'm pretty sue the 3" loaches would be eaten but since they spend majority of time on the bottom and when they come up it's in short fast bursts. So I would say it's possible they would live but possible they get eaten, I'm not too knowledgable about clowns but I heard they like a little salt in their water so I'm not sure if your other cichlids would like that.