ID please

[Hardrock]

Can somebody identify this. It’s growing on the overflow and in the sump.
Thanks

 

[fishguy242]

hi,believe white sponge

 

[dhanking]

Kill it it grows really fast

 

[samnaz]

that's a sponge

 

[Lovefish77]

It grew inside my cpr overflow to the point of stifling flow