What are these

[Jeffvt1999]

Anybody get these small white splotches one back, glass? Dint seem harmful but wondering what’s hatching?

 

[dwest]

Guessing spirorbids

Spirorbid Worms | Melev's Reef

Tiny white dots about the size of a pinhead can be found in reef tanks, overflow boxes, and sumps as well as on return pumps. They are Spirorbid Worms, which are filter feeders. It won't hurt to scrape them off if they obstruct your view, but they are harmless. This image is of their selfmade...

www.melevsreef.com

 

[Sisterlimonpot]

Guessing spirorbids

Spirorbid Worms | Melev's Reef

Tiny white dots about the size of a pinhead can be found in reef tanks, overflow boxes, and sumps as well as on return pumps. They are Spirorbid Worms, which are filter feeders. It won't hurt to scrape them off if they obstruct your view, but they are harmless. This image is of their selfmade...

www.melevsreef.com

That's my initial assessment as well.