worm 1/31/09 How's it going? <About as fair as can tell> I pulled this worm (it was floating around) out of my 120g reef while cleaning the tank. The worm is about 2-3 cm when stretched out and it diameter is less than a millimetre when stretched but fattens up when it contracts. Attached is microscopic pic. Could you identify it and should i be concerned of its presence? thanks <What nice pix! This is almost certainly a nematode/roundworm... Not likely deleterious, though I would remove it/them myself. This phylum is a huge assemblage of free-living to parasitic species... Much more on the Net. Thank you for sending this along. Bob Fenner>

- That's 'Todes, not Toads -
I have just noticed about 7-9 extremely small parasitic trematodes (or flukes) in my salt water reef tank. <Are they on your fish or around and about?> What can I do? <Not all 'todes are necessarily parasitic. Unless these are directly on your fish or you corals, I wouldn't be too concerned.> I just put my black percula into the tank yesterday after treating him with formaldehyde and malachite green for a week.  I just put the fish in the tank last night before I saw any of the trematodes.  I know they will begin to multiple and ruin my fish tank if left alone. <Not necessarily.> Although I do not have a lot of corals in there currently, what I do have is precious and currently I have no where else to place the corals to allow me to treat the tank with any solution. <Perhaps it's time to obtain such equipment.> It is a 29 gallon saltwater tank with an anemone, black percula, royal Gramma, 10 blue legs and scarlet reef hermits, one serpent star, and a couple corals (none of which have been purchased in the last 6 months).  The ammonia = 0, nitrite = 0, pH = 8.3, alkalinity = 8-10, calcium = 400ppm.
How can I prevent the spread and overgrowth of these unwanted parasites? <Again, I'm not convinced these are parasitic - there are only a couple of treatments that work against the 'todes and if you must treat, you'll have to remove all the invertebrate livestock from the tank. Fenbendazole, Piperazine, and Praziquantel are the most common treatments for nematodes and cestodes, but are typically administered in baths for the affected fish. I'd keep a very close eye on things for the mean while, looking for problems with the fish, not necessarily just crawling around.>
Jennifer
<Cheers, J -- >