bugs swimming in filter

[grdpder]

I checked my filter and can see white critters crawling or swimming inside my filter. I try taking a video of it, but didn't come out. They are around the size of an ant. Does anyone have any idea what they might be? If you do know, are they a threat to my tank?

Thanks in advance.

 

[Bifferwine]

They sound like amphipods. Amphipods and copepods (collectively known as "pods") are very common critters in our tanks, and are a sign of a healthy ecosystem. They make for good fish and coral food.

 

[dcantucson]

Here's some info on them:

Those Little White Bugs In Your Saltwater Aquarium Profiled - Classification Information and Facts About Copepods and Amphipods