Found in AIO chamber, what is it?

Badblackdog · Mar 7, 2026

I removed my protein skimmer and returned pump looking for the watchman goby that jumped into the AIO chamber and saw this crazy looking thing. The AIO chamber is completely dark normally so this is nothing that is photosynthetic. It is about 3 inches in diameter and about 2 inches tall. Any ideas?

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Tahoe61 · Mar 7, 2026

Cool Sponge, I believe.

Evil1 · Mar 7, 2026

Sponge

Badblackdog · Mar 7, 2026

Tahoe61 said:
Cool Sponge, I believe.

Yes, I confirmed it is a sponge and it is a great filter feeder. The fact that it’s so big indicates that I have a healthy system. I have some little tiny pineapple sponges, but I’ve never had anything like this size. It’s cool to find new stuff.