Alveopora question

[willforr]

So I’ve had this alveopora coral for 2-3 months now. No issues at all up until a week ago. It started closing up for no reason when all my other corals are doing fine. Any ideas for why this could be? My parameters are:
Nitrate: 5
Ammonia: 0
Nitrite: 0
Alk: 10
Calcium: 400 (currently raising it to 420)
Phosphate: 0
Salinity: 1.024
Please let me know, thanks

 

[Drich5150]

Believe they like dirtier water. Dont hold me to it.