What are these?

[Chuck S]

Are these Vermatid snails?, They grew out of nowhere UNDER my GSP mat. They can only be seen when the GSP retracts.

 

[ChiCity]

a sponge or tunicate of some sort

 

[Chuck S]

a sponge or tunicate of some sort

Thank you, I was just shocked when I did a water change and the GSP all retracted and they were all over...not there before...so for now probably a good thing

 

[vetteguy53081]

Are these Vermatid snails?, They grew out of nowhere UNDER my GSP mat. They can only be seen when the GSP retracts.

Poriferan sponge which is capable of growing and overtaking surface. Take the frag out and place in a container of tank water. Use a dental type pick or small crochet needle and gently pull off. Other option is to inject with air or vinegar via syringe which will stop it