Something to try is to place tall objects in the middle of the tank so they can have spots to hang out where they can't see the other fish. As Alley suggested, this is easier said than done sometimes, especially with fish this large - you don't want to use up all the swimming space with decor.
You could get a tank divider, or cut a piece of eggcrate (that white plastic grate material found in the lighting section at Lowe's) to fit. It is easy to cut to the exact size you need, and will allow water to flow through it. This is a temporary measure until you find homes for them.
They're gorgeous, by the way!
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