What Are These Shrimp Like Creatures?

I find shrimp like creatures in the filter water, what are they? Are they harmful?

 

I find shrimp like creatures in the filter water, what are they? Are they harmful?

Can you post a picture of them?

 

They could be scuds maybe.

 

I’ve seen people have brine shrimp in their tanks before, could that be it? I know they need brackish water, but I’ve seen someone with a freshwater tank have them.

 

Hopefully they're not Dragonfly Nymphs.

 

Too late already threw them away. They are about 3/16" long. I don't feed them anything that is alive.