Scoly sick?

brainreefspine · Aug 6, 2023

Hi all, everything had been pretty normal and stable in my tank until my cynarina started dying. Totally unexplained. Did some water changes and changed the carbon filter. Now all of a sudden my bleeding apply scoly is developing dark tissue on the outside. See photo. I just noticed it today. is this something to be worried about? Any ideas what causes this?

Tcook · Aug 6, 2023

What fish are in there? Do you have any emerald crabs?

brainreefspine · Aug 6, 2023

2 emerald crabs. 2 clowns, a flame hawkfish, flame back pygmy angel, and a royal gramma basslet.

Dipping it to see if that helps in DipX… lot of skeleton showing around the dark areas.

brainreefspine · Aug 6, 2023

Current state of cyarina in case it’s related

Tcook · Aug 6, 2023

My first thought was emerald crabs picking the edge. This happened to one of my scolys but it recovered. Wouldn’t explain recession around the entire piece. How long have you had it? Other lps doing well? What are nitrate and phosphate level?

Mr. Mojo Rising · Aug 6, 2023

I agree the crabs are my first suspect.

Tcook · Aug 6, 2023

Here is mine

And a thread on your other coral

EMERALD CRABS EAT CORAL

My Cynarina (button coral) was looking amazing. Then I noticed that it wasn't open and was closed a little lop sided and tight. Today, it was still closed and I noticed my tiny emerald crab nipping at the Stony base of the coral. Then I noticed that it was receded - but not receded half...

www.reef2reef.com

brainreefspine · Aug 6, 2023

candy canes, torches, and hammers are doing great. have one plate coral that's thriving and one that died about a month ago of unknown causes.

Phosphate < 0.25 according to API
Nitrate 0 according to API

I just put both corals in plastic cups in case it is the crabs. Do you think this is sufficient protection?