What is this? Sponge?

[xtsed01]

Hello, can anyone help me with identifieng?

Thanks in advance

 

[tbrown]

Doesn't look like a sponge to me. Does it move or is it attached to the rock?

 

[KJ]

Hello, can anyone help me with identifieng?

Thanks in advance

Cucumber.

 

[langhuang]

Cucumber, they eat Algae

 

[xtsed01]

Doesn't look like a sponge to me. Does it move or is it attached to the rock?

It moves and changes shape a bit

 

[xtsed01]

Cucumber.

Thank you, cucumber was my second variant

 

[xtsed01]

Cucumber, they eat Algae

Thank you, great)