Hollywood stunner turning white on the edges

[Coral Lab]

Hello everyone!

I got a hs chalice about 2 months ago for my 75 gallon mixed reef and it has been doing great and growing like crazy. Recently, as of last week, I noticed it has been turning white around the edges. All my other chalices and lps are doing great and none of my acros have been showing signs of stress as well. Any thoughts about what's going on?

 

[Daddi0]

New growth

 

[Randyz]

Yep I 2nd that. New growth for sure

 

[Optionman]

give that a lot of room because it won't stop growing. i bought a palm sized piece 15 months ago and its more than tripled in size. nasty stingers too.

 

[ReefkeeperZ]

looks like the edges are receeding if you look really closely at the pictures you can see the tooth pattern of the skeleton sticking through bits of the edges. Time to do some testing.
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