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[Julian.Rad17]

Weird thing that just showed up on my zoas in the past weeks

 

[SeaCucumberFan]

Maybe sponge

 

[Argo747]

My guess would be sponge, too.

 

[Julian.Rad17]

So it's not bad if I leave it?

 

[tazdvl]

If it is a sponge it's all good. I'd be more worried about the bright red arrow thing in your tank

 

[Julian.Rad17]

Yea I might need to take that out.