What is this

[Renaissance corals]

Just noticed a few of these today. What are they?


(Didn't come off with a toothbrush)

 

[JGT]

Spiorbid worm. Can be scraped off.

 

[KrisReef]

Entrance to the time tunnel or a spirorbid worm

 

[Renaissance corals]

Spiorbid worm. Can be scraped off.

I figured i could scrape them off. Are they good or bad?

 

[ISpeakForTheSeas]

I figured i could scrape them off. Are they good or bad?

Personally, I’d say they’re neutral - they’re tiny feather duster worms (filter feeders), so they don’t hurt anything. However, they’re populations sometimes get pretty big, and some people think they’re unsightly.

 

[JGT]

Not bad, just annoying.

 

[Renaissance corals]

Personally, I’d say they’re neutral - they’re tiny feather duster worms (filter feeders), so they don’t hurt anything. However, they’re populations sometimes get pretty big, and some people think they’re unsightly.

As long as they don't clog filtration badly, I'll scrape them off the glass whenever I feel like it. It's a frag tank so I'm not too worried about it