I have these guys in my rocks near monti plates. All acros doing ok but my monti plates are not great so looked more closely, they look like a type of flatworm?
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Thanks. I’ll catch more and see if I can get a better pic. They are small so difficult. They scoot along the surface like I’d assume a flatworm would. Maybe a type of planaria?Really hard to see... if you can't get better images, maybe you can describe how they behave/move? Are they fast? Are they slow? Do they move at all? Do they crawl along the container or do they actually swim through the water?
If you fear they are attacking your montipora plates you might want to check if you can see them actually sitting on or under the plates, where they could potentially cause harm. Maybe you will see more once the lights go dim/out. You could wait 1 hour past lights out and then check with a flashlight if there are more and if they start crawling onto your montis.

Thanks and similar answer to Google image search, likely them. They aren’t in plague proportions yet so I can keep a way on them as well as siphon out here and there. I do have some mandarins that may be eating them, not sure. I’d do a six line wrasse but I think that will not make the mandarins happy long term :/I assume Convolutriloba retrogemma (Red Menace / Acoel Flatworm)...? Looks definitely like some bad guys you don't want in your tank, even if my identification isn't fully correct![]()
Those things can explode in numbers and hide really well... I would look for actual treatment options and I doubt you will be able to remove all by hand.Thanks and similar answer to Google image search, likely them. They aren’t in plague proportions yet so I can keep a way on them as well as siphon out here and there. I do have some mandarins that may be eating them, not sure. I’d do a six line wrasse but I think that will not make the mandarins happy long term :/I assume Convolutriloba retrogemma (Red Menace / Acoel Flatworm)...? Looks definitely like some bad guys you don't want in your tank, even if my identification isn't fully correct![]()
Yeah, definitely in the Convolutriloba genus with that tail-end; I don't know how to tell the four species apart at this point, but not a keeper regardless.I assume Convolutriloba retrogemma (Red Menace / Acoel Flatworm)...? Looks definitely like some bad guys you don't want in your tank, even if my identification isn't fully correct![]()
Oh ya I have a lot of these now that I know what I’m looking for. I may have to go FW exit but nervous on it with the toxins.Bummer :/ ya seems like planaria. I’d like to avoid chemicals so may try a wrasse first and see if it reduces them some. I suppose I could hit it with FW exit while population is low but nervous on the impact to other beneficial creatures.