please ID the white objects

[yraveh]

Good afternoon.
my overflow is full of these white objects about 12 mm X 4-5 mm.
they don't seem to move. they are anchored to the walls or pipes. they surely look like living creatures.

what is it please, and Is it good or bad?

Thank you
Yehuda

 

[dalston]

Pineapple Sponge - harmless filter feeders.

 

[Remy LeBeau]

The little white dots are Spirorbid worms. These are harmless as well.

 

[mcgyvr]

Yep.. Pineapple sponges and the white circles/spirals are Spirorbid worms

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