Parameters are solid... but corals disagree

[Salt1972]

Our parameters seem to be on target.

79.9 deg F
1.026 Reef Crystals
516 Ca (Hanna)
9.0 Alk (Hanna)
1480 Mag (Nyos)
.037 PO4 (Hanna)
2 NO3 (Nyos)

Over the last 3 weeks, our prior thriving Sunset Monti slowly turned milky white and died and our Maze Brain receded and is only hanging by a thread. Now, our Jingle Bells Cyphastrea is fading. The caleurpa in our refugium is retracting also.

Any ideas? We did a 30g water change (of 125g system) today. I'm not sure what else to do.

 

[kashman100]

How's your flow? Have you reached in the tank after using sunblock lately?

 

[Salt1972]

Flow has been consistent. In a 6' 125g, we have ~10x turn over from return pumps and a Jebao PP8 on each end. The LPS - GSP, Duncans, Frogspawn, Torches, etc. are continuing to thrive.

I'm not aware of any sunblock contamination, but that's a good reminder. Thank you.

BTW - Lighting has not changed. (4) Kessil 360's on a consistent schedule.

 

[Cory]

Id suspect copper or some other toxin. Do you have aby stray voltage? Rusting magnets? Used a new bucket of salt? Did you add any new equipment?

 

[Salt1972]

Copper - I've never had any copper near the system.
Rusting magnet? Possibly. I have an old powerhead in my refugium to keep it stirred / clean. I'll check.
Stray Voltage? I'll get a meter and check. Wouldn't that have an effect on LPS too?
Salt? -- Always Reef Crystals and we've been on the same box since January.
No new equipment.

Only exception is we have far fewer fish thanks to a terrible accident in April. The corals have been growing after recovering from the initial shock of that accident. I don't think this reaction could be delayed, especially after seeing growth since.

 

[Cory]

Copper - I've never had any copper near the system.
Rusting magnet? Possibly. I have an old powerhead in my refugium to keep it stirred / clean. I'll check.
Stray Voltage? I'll get a meter and check. Wouldn't that have an effect on LPS too?
Salt? -- Always Reef Crystals and we've been on the same box since January.
No new equipment.

Only exception is we have far fewer fish thanks to a terrible accident in April. The corals have been growing after recovering from the initial shock of that accident. I don't think this reaction could be delayed, especially after seeing growth since.

The stray voltage could indicate a spliced wire was exposed to water and leaked copper. Id check all magnets or metal in contact with water. Algae magnets too.