Alien in my tank!! What is it????

[Dalbery]

I was just watching my suncorals coming out and saw this thing making tracks across my sand floor. It is thin as a leaf and can contract and expand quite a bit in length. Can someone please tell me what this freaky thing is and if it's a good or bad thing?
Thanks in advance

 

[bodycology21]

No idea man, never seen anything like it. good luck with the id. I will follow along as i am curious as to what it is myself.

 

[Skimmy]

flatworm.... several species get large like that, ...
omnivore that will eat alot of different things,
could possibly nibble on things.

one started slithering on me when i grabbed some live rock out of a tank,
scared the crap out of me and chucked the rock across the room..
it looked like a moving clam mantle...lol

 

[returnofsid]

They are a predatory flat worm, typically eating snails or clams. Leslie can fill you in on the details. I'll move this to her forum.

 

[Skimmy]

vicious little beasty, i knew they ate something, couldnt remember.
mine went in the toilet. felt bad, but... OUT!!!
would love to hear more about them.

 

[Dalbery]

Is there anything that will kill them? It must have been in my tank for a while and this is just the first time I've seen it so there's probably more It doesn't seem to be picking on my clams yet.

 

[NWDiver]

Cool! I'm looking forward to the info as well.

 

[thatguy559]

agreed upon first sight i immediately though flat worm

 

[returnofsid]

As far as I remember, from when I found one, and Leslie gave me advice....

No, there's not a chemical or medicinal treatment. You'll need to manually remove it. One good thing is, these are sexual, as apposed to asexual. So, basically, they need two to tango. So, there's a good chance that you don't have a 'colony' of them, reproducing, as you could with some other types of flatworms.

 

[Krish]

Buddy, if I saw something like that in my tank, I'd yank it out right away!! :lol: I'd imagine something that size would need to be manually removed. Did you remove it or just let it stay till you got an ID? Usually a good piece of advice for finding anything in your tank you aren't sure about is move it into your sump/fuge if you have one, until you get some info on it. That way, if it is bad, you can do away with it and not have to go searching around to find it in your tank as some things go un-seen for weeks once out of sight!

 

[LeslieH]

Hi guys --

Everyone who said Flatworm stand up & take a bow. It looks a bit different than the usual mollusc-eater which we call Pericelis. Pericelis will swallow small snails whole, digest out the animal, then spit out the shell. With bigger molluscs it will evert it's proboscis, secrete digestive fluids, then suck up the semi-dissolved goo. Using this technique it can chow down on animals as large as Tridacna. They must be able to scavenge/prey on other items/eat detritus as they can survive for months without molluscs in a tank. I see you have a Tridacna. If it or your other molluscs haven't been attached then this definitely isn't Pericelis and might be harmless.

Polyclad flatworms like this one are hermaphrodites and yes, it takes at least 2 to tango. It's the small ones like red flatworms that reproduce by budding off new ones - that's why they can take over a tank so quickly. Odds are you do have more of them in the tank. They tend to live in crevices & on the undersides of rocks. The coloration allows them to glide by unnoticed most of the time. Many species have defensive chemicals so it might take a specialized predator to go after them. Flatworm Exit will work if you see more than one.

 

[DTECH07]

Wow that's some good info to know, Thx Leslieh but i'm with krish: "If I Don't Know It's Gotta Go!".

 

[Dalbery]

Thanks Leslie Is flatworm exit reef safe?

 

[LeslieH]

it is unless you overdose. Too much and other animals will be affected as well. There are tons of posts about flatworm exit and other ways to get rid of flatworms along with their pros & cons on this & other boards.