What is this orange base under my zoo's?

[Shobloth]

Can't tell if its a sponge or something else, thoughts?

 

[cloak]

My guess would be a sponge as well.

 

[xnetgeek]

yes, it's sponge, and very good for your tank.. don't lose it.

 

[neuro]

yes, it's sponge, and very good for your tank.. don't lose it.

Sponges can compete for space and even grow over the mat of a zoa colony.

How do I know this? Because it's happened to me. It got way out of control.

 

[650-IS350]

you can use tweezers to rip off the pieces of sponges you want gone. Yes I've had sponges grow inbetween colonies/frags or even grow over frags killing them.