HELP! Unknown white sac suddenly appeared

Debora C Berg

New Member
I have a new white sac looking thing in my reef aquarium. Was thinking egg sac?

I have 3 brittle stars, two clowns, and a variety of other fish. IMG_20201003_183950.jpg


Well-Known Member
Does this move? if so it looke like a nudibranch to me. If it keeps to one place, it might be a small sponge.


JoePa lives on!!!
Staff member
Maybe a few other pics if you can. Could be a sponge or if moving, as Dave said, possibly a nudibranch