explain this phenomenon

[djp183]

Ok, so my green sinularia always shrivels up for a few hours at about noon. All my other corals have nice polyp extention throughout the day. Also, the sinularia has been getting little black dots on it that I cannot identify, but suspect they are related to the first problem. Anyone have any ideas? Thanks.

[Neon]

gonipora does it to

[tinyreef]

do the little black dots move? are they the same size? shape? do the black dots tend to congregate in one area or spread somewhat evenly? do they disappear and re-appear the next day?

 

what are your other corals? types? do you have a pic to show the layout/setup? could the black dots be carbon dust leaking out from your filter media? is the sinularia close to the filter output?

 

sinularias tend to slime more and not shed their slime coatings as fast as most 'typical' softies (e.g. most sarcos, alcyons, etc.). not that they would do better with more flow but rather they'd do better with less irritants, period.

 

i'm more than just curious because i'm in the middle of a 'partial meltdown' of a big (18" tall x 18" wide) green sinularia myself. it had been fine for a long time, growing well (from about 12" x 12" plus multiple fraggings), and slowly creeping up the LR. suddenly, it started to show signs of sickness after i returned from a short biz trip (two days).

 

what's unusual is that there are two daughter colonies in the same tank that are doing fine. plus, the disease seems to be only situated on one side. i have suspicions but no hard proof.

 

your coral's cycle of deflation at around noon is very unusual. ime it points to outside stimuli rather than internal. e.g. automatic feeder, outside lighting, heating/AC, human interference, so on. check into anything that may coincide around that time, for instance even an alarm clock. the coral can feel vibrations. hth

[djp183]

I guess that they are just tempremantal corals. My little black dots aren't uniform in size or shape; they appear to be random in terms of where they appear on the sinularia, and only appear shortly after the coral has started to get 'better' and expand. I'm ruling out the carbon dust because I keep that in a bag in my sump. ?hmmm?