In that case since you're seeking help and not on a seek and destroy mission you have to give corals space. Corals like euphyllia (hammer, torch, frogspawn) galaxia, goniopora, and other similar corals send out fighting "tenatacles" or nemotocysts. It is tricky since these can come on at night when the lights are out and you're asleep. I don't think anyone can give you a magic formula how far apart to spread your corals. It depends on the current in your tank. Understand nematocysts can be far longer than regular tentacles. You may think you're giving enough room and all of a sudden you witness coral damage.