Acro Mesenterial filament/nematocysts troubles

[seth&angelle]

So I have two acros that are spilling their guts daily like they are constantly at war few months. It’s really puzzling to me because there are not any corals close enough for them to sting. First I thought the corals were stressed and likely going to start having tissue necrosis, but surprisingly the two acros are growing well and are coloring up nicely. The filaments go back into the coral at night and are out all day with the lights on. My parameters are unchanged and my alk is extremely low but has been for most of this year. Here is a link to my low alk. I questioned the risks of my low alk and so far I haven’t noticed anything detrimental. Unless the low alk is starting to cause these two acros to be at constant war with nothing. https://www.reef2reef.com/threads/crazy-low-alk-but-my-corals-look-better-than-ever.555766/
So the corals in question are a PC Rainbow and mango rainbow something or other? Has anyone every experienced this behavior for no apparent reason? The pictures don’t show the filaments as well as I can see them in person. If you zoom in you can make out the white stringy stingers/guts.

 

[seth&angelle]

More zoomed photo.

 

[Justfebreezeit]

That's pretty gnarly. Do you feed anything/dose anything that would elicit a feeding response?

 

[seth&angelle]

I have an auto feeder that has hatchery diet pellets and reef roids.

 

[HB AL]

They look great, I wouldn’t lose any sleep over it.

 

[SeaDweller]

Yup. When one side of my RMF red devil nasuta started to look bad with thin tissue, mesenterial filaments expressed like crazy for a few days on the thinning side. I thought I was going to lose the piece. I left it alone and the tissue is starting to heal in those areas. Don’t know the cause, but I wouldn’t change the whole system for one piece. You can see the damage in the left side of the piece. That side was all filaments not too long ago.

 

[seth&angelle]

There no damage that I can see. This has been every day for several months.

 

[SeaDweller]

Ime, there’s some stressor that’s causing expression but I may be wrong.

 

[seth&angelle]

Ime, there’s some stressor that’s causing expression but I may be wrong.

Maybe so. Just trying to figure out what it is causing them to want to fight.

 

[Graffiti Spot]

When they do this after I feed and it’s the same few corals I take it as a feeding response but when it’s paired with other stress factors like paling, browning, or necrosis at random points in time then I worry.
Is it only happening when food is in the water column?

 

[seth&angelle]

It’s the entire day for a few months now.

 

[DesertReefT4r]

Thats odd for sure. Each time an acro did this it had tissue lose within days after, at least in my experience. Maybe the Reef Riods in the auto feeder are causing the responce but I have neber had acros respond like that to Reef Riods.