Any ideas? What is it...

[warhorseart]

So I got a rock with a couple of mushrooms on it. It has this white "plastic looking glob" when I got it home I felt it and it's actually soft, almost like a hard marshmallow. It's been in the tank about a week and today I noticed these holes open on it. What the heck?

Any ideas? Good or bad?
Thanks,
Steph

 

[ebushrow]

Sponge....as long as it doesn't start to choke out the shrooms it is ok

 

[Mike J.]

Chicken Liver Sponge? Aquarium Invertebrates: A Look at the Sponges ? Advanced Aquarist | Aquarist Magazine and Blog

 

[warhorseart]

Chicken Liver Sponge? Aquarium Invertebrates: A Look at the Sponges ? Advanced Aquarist | Aquarist Magazine and Blog

That must be it, so proud to have something called Chicken liver in my tank. ROTFLMAO! Well, I will leave it be for now. The mushrooms were shriveled and sad when I got them, now they are doing great (fat and happy) do I'm guessing the CLS ( sounds better) isn't bothering them. Thanks for the info!