Are these harmless or problematic?

[Adam1985]

Hi all,

In relation to ticked off corals from time to time, coupled with being able to sleep late and wake up late (vacation for the holidays), I’ve been looking at my tank more at night, i.e. during total darkness.

I noticed quite a large population of these, and they seem to be congregating the most around montipora species. One of those was quite angry not long ago for reasons unclear to me.

Any idea what these are, and more importantly, are they harmless?

I can try to take more pictures if needed.

Thanks,

Adam

 

[Zach B]

Look like amphipods. If they have enough food they usually don't bother corals but others have had negative experiences

 

[Eagle_Steve]

Hi all,

In relation to ticked off corals from time to time, coupled with being able to sleep late and wake up late (vacation for the holidays), I’ve been looking at my tank more at night, i.e. during total darkness.

I noticed quite a large population of these, and they seem to be congregating the most around montipora species. One of those was quite angry not long ago for reasons unclear to me.

Any idea what these are, and more importantly, are they harmless?

I can try to take more pictures if needed.

Thanks,

Adam

View attachment 2471362

Gammarid Amphipods.

Typically not harmful and good micro algae eaters. They are also a tasty snack for most fish. They can annoy some corals, but typically do not eat any, as long as there is some algae present.

 

[KonradTO]

Its amphipods. Apparently some fish eat them but in my small 32g I have far too many despite the sixline hunting all day long. Some people found them munching on zoas..I had a zoa head eaten and after that I raised my zoa frag from the sand, just in case..