Acans favias etc slowly receding

[Cherim7]

Can anyone tell me why several of my acans and favias recede? Over a slow period of time though. Like a year or more. Attached one pic for you to see. Are there any supplements that could help etc? Parameters are quite constant, check it weekly and try keep it to this

Mg 1350
Ca 450
Sg 1.025
Kh 7.8
No3 5-10(trying not to let it drop too low)

 

[reaper0268]

Do you feed them?

 

[Cherim7]

Do you feed them?

Reef roids yes

 

[hyprc]

Any new additions in the last 6ish months? A frag a rogue crab could've come in on? A Foxface that ran out of its favorite algae? To me that looks like something's picking at it.

 

[Hemmdog]

Try feeding them some mysis.

 

[JohnMzreef]

I think you have a bad actor in your tank because there is a focus of damage but the rest of the coral looks decent.

 

[Reef Bazaar]

could be a fish/invert nipping or eating it, or could also be flow. You mentioned that you feed reef roid // as with when feeding any coral, whether spot or broadcast, food can get stuck where it can't be consumed, and usually good flow is what helps get it back in the water column. If there is not enough flow, the food can rot on the coral itself, potentially causing an infection, or the sitting food can be an invitation for your CUC to come and annoy your corals..

Only two things I can think of if your params are stable.

P.S.: do you dose kH? if yes, how often do you do it? Because while your number is great, it's the swings that can affect the corals more than the number itself ..