These appeared overnight in numbers...

[Morpheosz]

These guys appeared overnight in the dark areas of my sump. Didn't notice them in the fuge that was lit overnight. I dumped a heavy feeding of phyto, reef chili, and aminos in before the lights went out, maybe that spurred them? They are a bit hard to make out but there are quite a few. Hoping they are benign! Thanks in advance for any thoughts.

They are very hard to get the camera to focus on as they are only a couple millimeters long at most.

 

[Gtinnel]

Looks like pineapple sponges. They're harmless.

 

[ying yang]

+1

 

[Morpheosz]

Looks like pineapple sponges. They're harmless.

Excellent, thank you! Do they grow, or is this what they are? I assume they are filter feeders that might have been happy with my food dump.

 

[Gtinnel]

Excellent, thank you! Do they grow, or is this what they are? I assume they are filter feeders that might have been happy with my food dump.

They stay small. They're common in newer tanks and usually eventually go away on their own.