So I’ve had this 15 gallon reef up for over a year now and everything has been growing great no problems so to speak of until about 2 months ago when one of my Acan colonies started acting strange.. Its two oldest polyps (the two I bought it with) are sunken and sad all the time… it behaves fine even puts out feeders into the water at night, eats well, all the polyps look good, and has even put out two new polyps recently… and every other coral looks good and are growing vigorously as well.. but those two just act upset all the time. I have tested everything within my capability and as far as I am concerned all parameters are the same as I always keep them. Flow has not changed, lighting has not changed (AI Prime). Nothing has been added for at least 6 months. Any ideas would be appreciated as I cannot figure it out.
Temp: 78
Ammonia: 0
Nitrite: 0
Nitrate: 10
Phosphate: 0.03
Salinity: 35PPT
PH: 8.3
Alk: 8.6
Cal: 440
Mag: - No Test
Temp: 78
Ammonia: 0
Nitrite: 0
Nitrate: 10
Phosphate: 0.03
Salinity: 35PPT
PH: 8.3
Alk: 8.6
Cal: 440
Mag: - No Test