Red planaria I think?

zfisk · Feb 17, 2026

I’ve saw some of these guys in my sump a few weeks ago but wasn’t able to grab them. Finally I was able to catch a few off a small piece of dead anacro that broke off and was laying in the sandbed. Is this red planaria or something else?

20260217_084712_9D4EA5EC-F482-4528-A47E-CC7707F1A131.png

View attachment 20260217_084728_85009996-0905-4879-B33E-B520C4779094.mov

View attachment 20260217_084739_AB61D681-C79D-48FE-A691-D3FF23BB3EAE.mov

Subsea · Feb 17, 2026

It’s not red Planaria. I don’t think it is a flatworm at all.

Tahoe61 · Feb 17, 2026

Nudibrach versus flatworm. Moves like a flatworm. Was it on the piece of Acropora?

zfisk · Feb 18, 2026

Tahoe61 said:
Nudibrach versus flatworm. Moves like a flatworm. Was it on the piece of Acropora?

There were 2 in this Tupperware, 1 fell off and one stayed on that dead piece of anacropora. Before I caught these, I first saw a couple in my cheato ball.

Additionally, about a year or so ago I had some pretty big colonies of easy sps.

They've almost all died now. I initially blamed it entirely on lack of maintenance but I'm now wondering if these guys had something to do with it. I had a pretty nasty elbow surgery that caused me to do minimal to no testing or water changes for several months.

zfisk · Feb 18, 2026

zfisk said:
There were 2 in this Tupperware, 1 fell off and one stayed on that dead piece of anacropora. Before I caught these, I first saw a couple in my cheato ball.

Additionally, about a year or so ago I had some pretty big colonies of easy sps.

They've almost all died now. I initially blamed it entirely on lack of maintenance but I'm now wondering if these guys had something to do with it. I had a pretty nasty elbow surgery that caused me to do minimal to no testing or water changes for several months.