Please Help: Isopod Identification

[DanBeck]

Hello everyone,

I hope all of you are well.

I have had some copepods growing in my tank for a while, but I recently found some isopods.
I know that certain species are predatory and cam be a real problem.
Please can you help me identify if the species that I have are problematic.

Thank you!

 

[MnFish1]

where are they from? a ruler next to the pod would be nice

 

[DanBeck]

where are they from? a ruler next to the pod would be nice

They are from my filter.
The big one is approx. 5-6mm.
The small one is maybe 3mm