Little guy in my sump

[Greenjim]

Hello everyone!

Just wondering what this is? They hang out on this porous block and in my chaeto.

Thank you!

 

[MnFish1]

It looks (depending on what you mean) - like a sponge of some sort - can you provide a picture with an arrow directed at what you're curious about

 

[Greenjim]

Yes, sorry not the best picture. Heres a video, slowly moving arround. I have bristleworm is it a baby?

 

[MnFish1]

Yes, sorry not the best picture. Heres a video, slowly moving arround. I have bristleworm is it a baby?

Unfortunately - unless posted on YouTube - Cannot see the video

 

[s_tooz_123]

Iooks like a copepod to me. very beneficial.

 

[Greenjim]

Unfortunately - unless posted on YouTube - Cannot see the video

Here :

 

[MnFish1]

Iooks like a copepod to me. very beneficial.

I'm going to disagree - impossible to tell without the magnification, etc.

 

[MnFish1]

Its in your sump - let it stay there

 

[Soren]

By the appearance and the way it moves in the video, I have confidence in the identification that it is a gammarid amphipod.
They are generally considered beneficial omnivorous clean-up crew members and free fish food, though I have heard of issues with them becoming invasive for some (though I think this implies too much food source/overfeeding) and sometimes irritating corals. They tend to be most active at night to avoid predation by fishes.

 

[WheatToast]

Iooks like a copepod to me. very beneficial.

By the appearance and the way it moves in the video, I have confidence in the identification that it is a gammarid amphipod.
They are generally considered beneficial omnivorous clean-up crew members and free fish food, though I have heard of issues with them becoming invasive for some (though I think this implies too much food source/overfeeding) and sometimes irritating corals. They tend to be most active at night to avoid predation by fishes.

+1 on amphipod. These are considerably larger than copepods and resemble small shrimp.

 

[WheatToast]

I'm going to disagree - impossible to tell without the magnification, etc.

Copepods and amphipods can be differentiated by their body structure:
Amphipods are generally darker in coloration with curved backs and multiple prominent legs on their underside. At the front of their body, they have two eyes, antennae, and, occasionally, two very prominent, club-like pincers. They are also easy to photograph with a phone camera.
http://www.saltcorner.com/Books/BookPics/Amphipods in my aquariums.jpg
Copepods are generally lighter in coloration and resemble rice grains with two prominent antennae, a tail, and no prominent legs. They have a single eye at the front of their body and often have a pair of egg sacks at the back, next to their tail. Their small size makes them nearly impossible to capture with a phone camera.
https://www.3reef.com/data/photos/l/4/4731-1253211854-583729211a3a13b8792fa3b4683b10f2.jpg

 

[besskurz]

Looks like an amphipod.

Copepods are like this

 

[WheatToast]

Copepods are like this

Not copepods. These are munnid isopods, which are beneficial grazers. These grow larger than copepods but do not have curved backs like amphipods.

 

[MnFish1]

Copepods and amphipods can be differentiated by their body structure:
Amphipods are generally darker in coloration with curved backs and multiple prominent legs on their underside. At the front of their body, they have two eyes, antennae, and, occasionally, two very prominent, club-like pincers. They are also easy to photograph with a phone camera.
http://www.saltcorner.com/Books/BookPics/Amphipods in my aquariums.jpg
Copepods are generally lighter in coloration and resemble rice grains with two prominent antennae, a tail, and no prominent legs. They have a single eye at the front of their body and often have a pair of egg sacks at the back, next to their tail. Their small size makes them nearly impossible to capture with a phone camera.
https://www.3reef.com/data/photos/l/4/4731-1253211854-583729211a3a13b8792fa3b4683b10f2.jpg

I stand by what I said. I never commented on copepods vs amphipods. I said I disagreed with what someone said - because the magnification was not posted

 

[vetteguy53081]

Hello everyone!

Just wondering what this is? They hang out on this porous block and in my chaeto.

Thank you!

This is an amphipod- member of copepod group but a little larger

 

[EeyoreIsMySpiritAnimal]

Iooks like a copepod to me. very beneficial.

Amphipod... Copepods are much smaller