Monti, acans dying, other corals appear good

[RabidDragon]

Issue: 3 Acan corals, a bubblegum Digitata Montipora and a Trachy all suddently retracted to the extreme. The acans and monti had been doing very well and growing. The Trach was purchased and introduced (I believe just days after the acans/monti retracted).

All other corals (~60) appear to be happy and growing.

After a month of complete retraction the 3 acans have died. The Monti and Trachy show no sign of change.

I've been running carbon for weeks thinking it might be some toxin but it hasn't helped.

What would specifically upset these corals but not others?

ICP test results are all in green with exception of Lithium which is elevated/ yellow grade: 332, reference range: 0-200.

sg 35
alk 9.0
nitrate 15
phos .07
Ca 425 (trying to raise it a bit)
Ph 8.0 - 8.3

Historically the Nitrate was in the 30's and Phos was 0.3 - 0.4 and I've been successfully been working to bring this down. All corals were happy with these levels but GH algae was taking over.

Thanks for thoughts

 

[Cichlid Dad]

You need to give more information.
What is your set-up. Size, age, lights flow. History on the coral. Both doing good and dieing. Water source. Water change schedule. What are you dosing. Fish and invert stocking list. Anything you have recently changed or added.

 

[Mr. Mojo Rising]

more info and pics help a lot.....

 

[Gregg @ ADP]

Issue: 3 Acan corals, a bubblegum Digitata Montipora and a Trachy all suddently retracted to the extreme. The acans and monti had been doing very well and growing. The Trach was purchased and introduced (I believe just days after the acans/monti retracted).

All other corals (~60) appear to be happy and growing.

After a month of complete retraction the 3 acans have died. The Monti and Trachy show no sign of change.

I've been running carbon for weeks thinking it might be some toxin but it hasn't helped.

What would specifically upset these corals but not others?

ICP test results are all in green with exception of Lithium which is elevated/ yellow grade: 332, reference range: 0-200.

sg 35
alk 9.0
nitrate 15
phos .07
Ca 425 (trying to raise it a bit)
Ph 8.0 - 8.3

Historically the Nitrate was in the 30's and Phos was 0.3 - 0.4 and I've been successfully been working to bring this down. All corals were happy with these levels but GH algae was taking over.

Thanks for thoughts

Did the retraction coincide with lowering your PO4?

 

[kevgib67]

Magnesium?

 

[BitReef]

Did the retraction coincide with lowering your PO4?

This. Have you had major swings in phosphates recently? I was actively reducing my PO4 with gfo and running my skimmer (which I normally don’t run). Reducing my PO4 by over 50% in a few days. This coincided with a sudden loss of 60% of a large green monti.