Something Growing in Sump

[tmecfowlr]

I read through the pinned ID posts but couldn’t find anything that matched really well. Best guess is pineapple sponges but seems different to me.

Just noticed these growing on the sides of the sump today. The larger more established ones seem to be growing a projection out from the center.

Didn’t notice any growth during weekly water change and maintenance on Saturday. No lights in sump chamber either. Tank itself is about 3.5 months old and currently in the ugly phase with some significant cyano outbreak on the sand bed.

 

[bossman818]

They look like sponges. Kinda hard to tell. I have some on my clam so I am sure they are harmless.

 

[ErikVR]

Looks like pineapple sponges to me. Harmless feeders that you most often find in sumps as they don’t like light. Mine disappeared when I installed a refugium light in the sump.