Copopods or flatworms?

[oceanna]

I’m new to saltwater aquariums. I received corals two weeks ago and they’re still in my corantine tank. Recently, I’ve started seeing a small creature. I’m not sure if it’s a flatworm, copopod, or something else. Could you please help me identify it? Is it safe? Should I remove it to prevent it from entering my main aquarium? Also, I want to mention that my corantine tank has experienced a significant increase in diatom algae.

 

[Elira_6301]

Does it bounce around erratically or just crawl?

 

[oceanna]

As I can observe, it bounces erratically and rapidly on glass. However, some of them don’t move.

 

[Elira_6301]

I believe those would be amphipods. They can come from using live sand. Did you use live sand?

 

[oceanna]

This is a sterile quarantine fish tank with no sand or life rocks. There are just new coral fragments in the aquarium, which have been in it for two weeks.

 

[Üter]

This is a sterile quarantine fish tank with no sand or life rocks. There are just new coral fragments in the aquarium, which have been in it for two weeks.

 

[Üter]

I think they are pods that hitch hiked in on the coral. the tank was sterile till you added something from another tank.