how do sps settle real estate disputes?
 

i was looking at a friends tank and he has a lot of sps corals that seem to be growing into each other.

what happens when one sps touches another?

either one or both kills the other, or they just merge into each other.

is it like propagating a branch from one apple tree and merging it with different kind of apple tree?

will it create a new strain of coral?

No, one will just grow around the other, carrying on the other side. But usually one will kill the tissue it contacts on the other.

ok gotcha, thanks

Here's a thread with some great photos: http://thenanoreef.co.uk/forum/showthread.php?t=9841

What happens when Palys and Zoas grow into each other?

Usually nothing. Often though one is faster grower than the other and can smother the other. Usually it is bigger polyps smothering smaller polyps, but not always.

OK, as long as the Palys don't kill the Zoas by stinging. I can always trim back the Palys a bit. I just don't want to lose any of my Zoas.

I would recommend you wear gloves.