Whats the deal with flatworms?

Ok So I know I hear they are are bad but why? I have noticed just recently that they are there. They probally have been there for along time. If I turn on the lights in the middle of the night I see a ton of them on the rocks and they scurry away once the lights are on. What is up with these things? I am redoing the tank so if I need to treat ill be doing it now. I just never knew what the deal is with them. Any imput would be appericiated. I tell you I have looked back over the last few weeks and thought at first ive just had bad luck but then I keep thinking im doing something wrong.......

 

some eat coral an some just keep multiplying till they cover the coral.use flatworm exit if they get bad.it worked for me

 

Thank you! none are over my corals at all. they seem to be all over the rocks. there is 350 lbs of rock in my system. I cant say enough that there is 20-30 on each rock when I wake up and turn the lights on each day.

 

+1 on the flatworm exit. The stuff actually worked as avertised in a very short time. Just be sure and have good size ~15-20 percent water change ready b/c they die. The stuff is a godsend though....

 

Most flatworms are completely harmless until they reach plague proportions. Generally I think if you have the kind that are not directly harmful if you control your nutrient levels in your tank their populations will generally wax and wane. You might see a bunch for a while but then they will die off.
Careful using chemical treatments, it doesn't work out for everyone as advertised.

 

+1 on being careful with medication. It sounds like you have the harmless variety. If they are reproducing quickly you may consider a fish that will feed on them. Many wrasses are fine candidates.

 

I have 2 six lines in the tank. I never have noticed them until recently. they are very small I would say in the mm not even cm they are tiny almost not seen. There are hundreds of them in the large ammount of rock. but only in the early am if I flick the lights on do I see them.

 

Do they look like anything out here?
Melev's Reef - Visual Identification

 

I found this monster in my tank. It had to be in there over a year without me seeing it. The only reason I found it was because I needed to break the rock it was deep inside. It's since been nuked (they can't survive bleach water )




Now according to the link given above, this is a predatory worm that eats clams. I have a clam now, but I did not have one up to the point I found and killed it. So it apparently does not require clam to eat...

I had a 6 line for almost a year... I never noticed it eating anything like this... doesn't mean it didn't happen though.

As far as I can tell, this worm was 100% harmless and in all likelihood beneficial to my tank.

Here's my thread on it if you're curious.

http://www.3reef.com/forums/id/id-ameoba-worm-79844.html

 

That's a really creepy massive worm you got there hehe.

I've heard that halichoeres genus wrasses are more likely to munch on flatworms but I'm sure it's always down to the individual and possibly how hungry they are.