sps tank heading for a crash :(

[kevensquint]

I've got the beginning of at least a semi tank crash underway. Only acroporas are affected, and only about half of those. The problem is unique, sliming, and losing tissue. But not RTN/STN. Over a period of a few weeks, first, polyps are not open, then they disappear. The entire colony seems to then shrivel as in the tissue loses its thickness and volume. Its like a very slow even disentigration. They went from the voluminous healthy gym guy look to an 90 year old war vet look.Not loss of tissue from the base or tips.I have been checking for AEFW and eggs, as well as red bugs etc... All clean. These are corals that have been growing like weeds for over a year now. Colors are excellent, in fact blue and green has recently intensified along with the health going down hill , (?)
My params are very stable and constant.
There was a small dip in Alk about month ago, but I doubt it was that since the situation is now getting worse by the day.
Ca -420
Alk-7.7 DKH
Mg- 1300
K- 410
NO3- 2 ppm
PO4-0.02 ppm
PH 8.1 8.3 (d)
S.g 1.025
A few possible hunches I have,
-low level copper, due to foods,traces in my two-part solutions ( I use tons) accumulating. I rarely do WC's cuz my organics are very low already.
-I popped a bunch of bubble algae a few weeks back that I was tired of looking at.
-I don't normally use carbon, possible chemicals from the zoanthids in my sump
I tried running carbon for the past 4 days, but problem is worsening. I put some cuprisorb in tonight in case copper is the culprit.
Ideas??

 

[ChrisKirkland]

What type of lighting are you running?

Run some Cuprisorb if you have it, it will turn blue if copper is in the system.

What other corals do you have in your tank that is doing well?

 

[alan.reef]

any magnet cleaner or frag rack in there? could be rusting magnet!!

 

[kevensquint]

Yes recent magnet frag rack addition. I'll check that. Porites,birds nest,damicornis, and montiporas are OK. Also acro stags are fine. Mostly bottle brush types are affected. Light is 250 Radium/ T5 actinics. This has been the lighting set up for the past 20 years. It ain't the lights

 

[PaleHorse]

stray voltage maybe?

 

[jackson6745]

have you calibrated your refractometer with a 1.026 solution? Calibrating to 0 with ro water is not accurate IME.

How old is the system? How large? I think it's a good time to start with a good water change routine, and an initial LARGE WC in an attempt to correct your current problem.

 

[MBMAX]

Are you sure you don't have AEFW ?
I had the same problem stags and Montis were doing fine. I looked for pets or bite marks did not see anything , then I decided to dip an affected acro in Bayer and unfortunately 2-3 flat worms came out.