Possible sponge?

[Jindypony]

Hi brains trust,
I found this while doing my cleaning and am just wondering if anyone knows what this might be. It soft like a leather coral in texture and 2cm long and 1cm wide at top

 

[Lorenzo Angotti]

That’s a tricky one to me it looks like some sort of shell less snail, does it move or stay stationary If it moves that will give you an idea if it’s an invertebrate

 

[Jindypony]

That’s a tricky one to me it looks like some sort of shell less snail, does it move or stay stationary If it moves that will give you an idea if it’s an invertebrate

Umm no movement at all which is why I thought it might of been a sponge. Not missing any snails in the tank either