Do different caulastrea corals sting each other?

[Seansea]

So I have a green neon trumpet coral with smaller heads that I have had for 2 years. It has grown nicely from 2 heads to about 20. Beautiful neon green color. I added a purple and green caulastrea coral with huge heads not too far from it roughly 6 months ago. As the big headed one has grown the small green one has started to die off on that side. The other side heads are fine. Is it possible that the big calastrea is stinging the smaller one? I put them together thinking they were same Type coral. Has anyone else had this issue with caulastre?

 

[Seansea]

The answer is yes. Caught the scoundrel in the act last night with lights out