extruded filaments

[thedoogan]

I have two small colonies of green birdsnest in QT which have been doing good and putting on a lot of growth. Lately they both haven't had the greatest polyp extension, patchy in spots. I noticed that they have been extruding filaments in between their polyps. What can this be a sign of?

It's normal not this closed up, the picture was taken after handling to coral for examination.

 

[hk855]

Usually those filaments are used to atack nearby corals and they will move like a spider web from one coral to it's neighbor and the next day there will just be skeleton left where it contacted. I haven't seen them that small though. It seems like the coral is under stress from something, are there any corals nearby? Try turning the lights on 2 hrs after lights out and looking for pests or anything you don't see with the lights on. It could also be a water quality issue check for high nitrates or possible alk swing.

 

[thedoogan]

There is a torch coral about 6-7 inches away, not close enough for sweepers. The other birdsnest is on a stairstep level below it.

salinity 35 ppt
Alkalinity 8.4
Calcium 420
Magnesium between 1360-1400
phosphates 0.04
nitrates 0.5

It could be an Alk swing issue because i'm manually dripping two part for my QT

 

[thedoogan]

No visible pests.