Pink Millepora losing colors

[Paolissimo]

A week ago I purchased what I think is a pink Millepora. When I saw it in the store, to me the small colony looked ok, not great but ok. It was $25 so I grabbed it. I took it home and under my lights it looked much better than at the store. All the top was pink. Within a few hours the polyps were extended. Now I been observing this coral every day and to me its losing colors, and other people in my house agree. What can i do?
PH 8.3 during the day drops to about 8.1 at night
Calcium 420
Alk 9.3
mag 1470
nitrate 0
phosphate 0.07

I don't test anything else, so I am not sure if this particular coral likes something that is missing in my tank.

 

[msderganc]

From the picture, it looks like RTN...

 

[DFW]

The pinkish colony on the left in the picture looks to be losing tissue from the bottom up. It looks like a maricultured colony to me. I have been doing very well with tank raised acros, and millis, but several maricultured colonies have done the same thing in my tank. I stay away from them now, and stick with tank raised corals, almost always starting with a small frag.

 

[hybridazn]

Is the plastic tag attached to the coral in question? If so than that usually means it is a maricultured piece. Most of the time they will lose color but overtime will start to color back up in your tank as long as the conditions are good. If the bleaching of the base continues to spread you will need to frag the coral away from the bleached part.

 

[Paolissimo]

All four are marine cultured, the coral in question is the one in the back to the left.

 

[duke62]

Yeah stay away from maricultured not worth the headache. Also i see you didn't remove the rock it came on. Bad idea those maricultured pieces carry a lot of pests