Some kind of sponge?

After that last episode where I posted about the "pod" that turned out to be an insect, I'm a little hesitant to ask about these. I think they might be some kind of sponge but would welcome input from someone a bit more knowledgeable. They are growing on the bottom of a stealth heater in a dark corner of the tank. I have two more of them on the bottom of an overhang on a piece of liverock. I also wouldn't mind knowing what those spiral things are that grow on the glass in that same dark corner.
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That is exactly what they are. they call them pineapple sponges because they kinda look like pineapples. Anyway, They are great for filtration.

Oh and the spiral things are tube worms. You will probably see little feather like things protuding from them. They are also filter feeders.

Thanks lilfishie!

am i the only one that loves sponges as much as corals or anemone?

No not at all. Sponge comes in some really pretty colors and some grow really pretty.

agreed, just think they get overlooked a lot...