Anyone know what this thing is

[Damian reef boi]

 

[Billldg]

Critters isn't my specialty, but that looks like a sponge of some sort.

 

[El_Guapo13]

A sponge with a microalgae wig, perhaps?

 

[flsalty]

Kind of hard to tell out if the water, but it does look like a sponge.

 

[Topekoms]

Def a sponge it is harmless

 

[vetteguy53081]

Chia pet!!

irs sponge with chaeto stuck to it
Drop it in your sump

 

[Damian reef boi]

Ok thanks

 

[Softhammer]

World war 2 mine for blowing up u boats?

 

[Damian reef boi]

World war 2 mine for blowing up u boats?

Yep look

 

[Damian reef boi]

Yep look