What are these ?

[amber3cat]

 

[twilliard]

tunicate's it appears

 

[amber3cat]

I knew I'd seen them before but couldn't remember what they were called thanks [emoji4]

 

[twilliard]

I knew I'd seen them before but couldn't remember what they were called thanks [emoji4]

any day!

 

[amber3cat]

Are they good or nuisance, is it a sign of good water conditions. Any advice appreciated [emoji4]

 

[amber3cat]

It's my boyfriends tank and he has allot of them just wondering whether it's a good thing

 

[Pola0502ds]

Those arn't sponges?

 

[Roboson]

Tunicates are similar to sponges in both needs and delicateness, but different animals. Good sign of water quality though.

 

[clowner]

They look awsome

 

[Hans-Werner]

I am pretty sure it is a sponge and not a tunicate. What you see is a sponge with a number of exhalation siphons (oscula). Colonial tunicates have a more even suface and you can also see the regular inlet openings. In sponges the inlet openings usually are very small and irregularly spread over the whole surface. Sorry, I cannot find better expressions since English is not my mother tongue.