Ok so I know all corals can change color for various reason with tank to tank. I have had this chalice since it was a super frag like literally one eye 1/8th of an inch maybe idk. It has 2 full eyes and one coming in probly 3/4 of an inch mow and this was about a year ago it is always pink with hints of purple and blue(here's mother colony http://www.reef2reef.com/threads/new-release-polkadot-afro-circus-chalice.126525/). Now to my point I haven't target feed alot of my corals how i like to with now flow in a while due to a busy I schedule. I decided to do it tonight and when I slowly and I mean slowly leaked out some zoo plankton on to this piece it turned completely green and blue mashed together(blue in some parts any green in others blending to a turquoise). Then when it was in assuming done eating it turned back to pink anyone have any thoughts as to why or if that's normal for some corals.
