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Saltwater Aquarium/Items in my live rock and tank


I have some very small, white, circular (some just half  or quarter circles), almost worm looking spots in my live rock and they seem to be spreading through my tank.  I don't see any on my fish and just wonder what they might be.

Hello Braxton:

From your description, (without seeing a picture), perhaps they are flatworms, which are often white in color, small and somewhat circular in shape. Type into Google's Image Search the keyword Saltwater Flatworms and see if this resembles what you have.

Natural methods of eradicating flatworms may include introducing flatworm eating marine life, including: mandarin dragonets, peppermint shrimp, and sixline wrasse amongst a few others...

There are formula's on the market that you can dose your aquarium with to help eradicate flatworms, however extreme caution should be practiced, as to not do more harm to your aquarium than good...

See the web page below from Orange County Aquarium Supplies in regards to a flatworm removal product called Flatworm Exit.

I wish you luck with all your future saltwater aquarium endeavors.

P.S. Let me know if Flatworms is what you have...


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David Ocreef


Technical saltwater coral reef related aquarium questions are welcome. Coral, invertebrate, and peaceful species of saltwater fish questions are welcome. Questions asked on Saturday and Sunday will be answered the following Monday. REMINDER: Please check the answers pool to see if your question has already been asked and answered. Questions typically are answered within a 48 hour period, however sometimes it may take longer.


I possess over twenty-five years of hands-on experience and knowledge in the ecology of aquariums. Beyond the traditional, I have successfully tested and sustained environments that have been uncharted territories for hobbyists, for decades. I am the first to admit I don't know it all because there will always be something new, amazing, and exciting to learn about, as discoveries are made. It's a hobby one can never outgrow, or grow tired of.

MASNA - Marine Aquarium Society of North America. Director of Orange County Reef Aquatics -

Publications,, and many others.

After High School, my experience and love of marine animals influenced me to take up studies in Marine Biology. Throughout college, I studied Microbiology with an emphasis on Marine Life, as well as numerous other sciences. I continued to advance in this hobby, by building a dozen or more saltwater ecosystems all utilizing Microbes as the major source of my filtration method.

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