What is this? Sponge?

[tanker99]

I've had someone say this was a sponge but it looks like something is growing under the clear sponge. I just recently noticed the tree looking thing growing today. Any ideas?

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[Themonsterisme]

Pretty sure it's a sponge

 

[Fishman007]

sponge, i have hundreds throughout my tanks, Look like any of these?

 

[tanker99]

Ohh ok cool. Thanks for the response! !!

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