Bristle worms?... and sponge ID

[SaltyNewbie]

Hundreds of these little guys come out during the night?

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[Scoopy]

Definitely bristle worms, not sure about the sponge, although my tank is full of it.

Sam

 

[SnowManSnow]

Sponges . yes.. not sure what kind. They aren't harmful, but IME they tend to populate when your water is a little dirty. Kind of an early warning symbol.

b

 

[SaltyNewbie]

Thank you for the replys. Do I need to be concerned about the number of bristleworms in my tank?