Identify (Pesky Platyhelminthes) 7/9/09
Hello,
I have been reading your site for years and it has helped me a lot...thank you. Now for my question, I have something in my saltwater aquarium. I cant figure out what it could be... It seems to be a single cell type algae or creature of some kind...but I've not been able to identify what it could be.
<Phylum Platyhelminthes:
http://www.wetwebmedia.com/flatworms.htm
>
I need to know if it is harmful to my tank or what?
<Mostly "or what".>
...my tank has been up and running good for about three years...everything in it seems to be doing just fine.. it has been in my tank for about a month now but seems to be multiplying fast and is now starting to cover my glass, live rock and sand...how do I get rid of it?
<Best physically removed, or via the addition of something that eats them, though the range of options here will depend on your aquarium and level of experience; see here:
http://www.wetwebmedia.com/pestflatwrmanthony.htm
http://www.wetwebmedia.com/fltwmcont.htm
>
hope you can help.. I've enclosed 2 picture the first is up close shot and the second you can see it on my live rock.
<To be honest, I've usually found these pesky flatworms come and go in pulses, perhaps related to ambient conditions; optimising water conditions, improving things like skimming, circulation and filtration, should tilt things in favour of other, more desirable organisms.>
Thank You
Kristi
<Cheers, Neale.>

Critter ID 5/24/09
Sorry crew for the not to informative email. Ok the tank is saltwater, and the only new additions lately have been orange mushroom and a chocolate chip starfish
< Chocolate Chip Starfish are not reef safe. The mushroom could soon become lunch if it or the starfish are not removed. http://www.wetwebmedia.com/ccstarcompfaqs.htm >
I only was able to get 2 decent pics of this thing on the side of my tank, but there are about 20 of them that I can see, to much rock to really see the back of the tank, but there could be more! Thanks for your help.
Kenny
< The animals in the pics are Red Planaria (Convolutriloba retrogemma).
Remove what you can. They thrive in high nutrient and low water flow. Lots of info here on Wet Web. Please read here.
http://www.wetwebmedia.com/pestflatwrmanthony.htm GA Jenkins >

Euphyllia Eating Flatworm? Polyclad – 4/30/09
Hi!
<Hi there, Cath!>
I've lost several of my Euphyllia corals in the last couple of months.
<Uh-oh>
This morning, I've found what I think is a kind of flatworm on many of my frog, torch and ancora pieces. With a close look and more attention, I saw that all my Euphyllia are literally infested by this ”little” (some are up to ½”) beast.
<Yikes!>
There are also a lot of yellow eggs around them. Here is, in a joined piece, a picture of the beast. The shot was not taken by me, but by a fellow reefer of my area who has the same problem. What exactly is this flatworm?
<Looks like a Polyclad of some sort to me (see link below for more info).>
Is there a way to get rid of them?
<Manual/diligent removal of all visible worms/eggs. In addition, check any and all other corals (and rockwork if possible) for further evidence and remove any you come across. I’d also put the corals, one at a time, in small tub or container with tank water, and using something like a turkey baster, blast any areas of dead skeleton/rockwork with water to hopefully dislodge any unseen juveniles.>
I've made a lot of searches and haven't found anything about it.
<That’s understandable. I looked everywhere and only found a couple of unconfirmed hobbyist reports related to Euphyllids and suspected Polyclad predation. Furthermore, I was unable to find any documentation, anywhere, confirming actual predation of any coral species by these worms at all. That’s not to say that it’s not possible however. Apparently, there’s a lot of information still needing to be discovered/revealed regarding these large worms. The general consensus is that they’re all predatory - consuming various colonial or sessile organisms such as Tunicates, Bryozoans, bivalves, barnacles, etc, as well as other small invertebrates such as amphipods, small snails, Polychaete worms, and even other flatworms. Also, some evidently feed on algae, especially diatoms, but only as juveniles. The problem with this situation is that unless you’ve actually seen the worms eating live coral tissue, you have to consider that their presence may be secondary/incidental. Perhaps the corals are dying due to one or several other reasons – for instance environmental issues (water chemistry, chemical warfare/allelopathy, etc), or due to fish/crabs, etc picking at them. The culprit could even be another type of flatworm (perhaps Acoels?) or something else entirely. The Polyclad flatworms could be there to prey on the real predator(s), or other incidental/harmless amphipods, etc, that have congregated to feast on the sudden bloom of algae and/or dying coral tissue. Admittedly, an infestation level of anything near a damaged coral doesn’t look good, but I’d rule out other possibilities just to be sure. I have to admit, if I were in your shoes, I’d likely err on the side of caution and remove as many Polyclads as I could. Had there been just one or two, I’d have left it/them, but in the case of many – bye bye!
I’ve got some links for you to read through. Here’s a similar situation: FAQ titled “Euphyllia Health issues / hitch hiker ID... likely allelopathy, env. 6/9/08”, at this link: http://www.wetwebmedia.com/carydisf7.htm
Allelopathy issues: http://wetwebmedia.com/cnidcomppt3.htm
Flatworms: http://www.wetwebmedia.com/flatworms.htm >
Thank you!
Cath
<You’re very welcome! Take care, LynnZ>