That's a good question. How does a coral that sends out sweepers identify other corals as competitors and not accidentally sting itself or its potentially nearby progeny?
I'm not an expert but I've done exactly the same thing w/ frogspawn and no ill effects.
Worst case scenario, put them together and keep an eye on them. If they don't get along, separate them. Frogspawn is tougher than it looks.
