What is this !!

[vinnyvin]

Hi. Can someone please I.d this pink stuff for me it's growing on my rock in sump

 

[4FordFamily]

Looks like a type of sponge to me. I'm no expert so I can't tell you which type.

 

[aaron23]

Agreed looks like sponge and now partially dead sponge

 

[bios]

Blue sponge, very beauty
Low light actinic better turn color to blue

 

[vinnyvin]

Ah ok thanks il leave it in their then

 

[Bozoman]

Definitely a sponge. Looks exactly like one of the sponges I had in my tank. Mine died when I moved the rock it was on and it was exposed to direct lighting. It definitely preferred well shaded areas. If you want to keep it don't expose it to air like that.