Disturbed Green Star Polyp coral

[seavashr]

Hello


Few weeks ago I bought a Green Star Polyp & Torch. The Torch opened right away while the green star did not opened for few weeks.

Parts of the star started to turn white (from pink).
Recently the coral polyps started to open in the remaining pink parts, especially around corners of the coral.

An area that turned white early now looks like a "rusted skin". A gentle blow of water cause the cover skin to pills of and an underlying purple layer got exposed.

What do you recommend?
Should I cut of the white, and "rusted" area to ensure the opening area won't be affected?

Thank you

Red circle shows the white area, and blue the area with oppening polyps.

 

[Mr.Diggler]

Post your water parameters.

 

[RockStacker]

It looks like parts of the GSP's mantle are dying off.
It could be due to disease or there is something in your tank that it does not like.

 

[Bifferwine]

Water parameters? What kind of lights do you have? Did you do a dip on the corals for pests before you put them in the tank?

 

[seavashr]

Hello everyone


PH: 8
kDH: 7
Ammonia: 0 ppm
Nitrite: 0 ppm
Nitrate: 40ppm (This never dropped bellow 10! System been running for 1year, 90 gal With Sump)
phosphate 0.25~0.5

No initial dipping but yesterday I bought dipping solution and I dipped it.

Also yesterday I bough a Flower Pot Coral (Goniopora lobata ) and a red sea star.
Just over night the sea star died, and the coral turned white and again the skin and polyps of FPC blows off like dust.

What could be it? The 40ppm nitrate? Then why the torch is fine?

Thank you

 

[Bifferwine]

Nitrates at 40 are high enough to kill corals and inverts -- especially stars, which are very sensitive to nitrates. You really want them less than 20 at all times, and less than 10 if you have corals or inverts. Do you use tap water? Do you have a protein skimmer? How many fish do you have, and what kind? What do you feed them, how often, and how much? Also, test for stray voltage:

Identifying, Locating and Curing Stray Voltage in a Saltwater Aquarium