Very small black moving "bugs" on Scolymia Australis "Button" coral

dej4n · Nov 9, 2021

Can someone please identify those small moving black dots on my Scolymia button coral?

If my calculation is right, the dots are very small, ranging between 0.04 and 0.06 mm. Which should be 10 times smaller than the Black Bugs, if I'm right. For scale reference, the head has 1 inch diameter.

The movement can be seen in this time lapse footage, taken over roughly 30 minutes:

LordofCinder · Nov 9, 2021

looks like regular copepods to me. Nice coral and nice video!

dej4n · Nov 9, 2021

Thanks, I was enjoying making the video when I saw the dots for the first time.

Sorry for not being more specific, it is not the copepods on the plug, but these dots:

TnFishwater98 · Nov 9, 2021

dej4n said:
Thanks, I was enjoying making the video when I saw the dots for the first time.

Sorry for not being more specific, it is not the copepods on the plug, but these dots:
View attachment 2413719

How are you filming this?

dej4n · Nov 10, 2021

TnFishwater98 said:
How are you filming this?

Full spec:

Camera: Nikon D5300
Lens: AF-S Micro NIKKOR 85mm 1:3.5G ED (VR OFF)
Filter: B+W 022
Light: 2 x Red Sea Reef LED 80 (blue ~40%, white ~15%)
Time laps 1000 frames, every 2 seconds: Raw 20.3MP (6000 x 3375); ISO 160; f/40; 1s; Daylight WB
Photoshop: Raw export to 4K TIF sequence rendered to video in 30 frames/s

dej4n · Nov 10, 2021

I just realized that the black dots are only visible if the video is watched in HD or 4K on monitor (phone is too small).

minus9 · Nov 10, 2021

If your corals are showing no signs of stress or TN, then I wouldn't worry. The micro fauna present in our tanks is a whole other world. In the 90's when I was using a display refugium with a DSB, I found myself looking at it just as much as my display. Nice sequence btw.

dej4n · Nov 10, 2021

minus9 said:
If your corals are showing no signs of stress or TN, then I wouldn't worry. The micro fauna present in our tanks is a whole other world. In the 90's when I was using a display refugium with a DSB, I found myself looking at it just as much as my display. Nice sequence btw.

Thank you! I'm just starting with the hobby, it's a huge relief to hear that this is OK. I was dipping all corals, thought without QT. So I was a bit afraid that something unwanted might slipped through.