What kind of flatworm?

[HClH2OFish]

Ok, my 25H has been up and running for 2 months now trouble free....LR has lots of nice coralline, pod population is huge and the only fish (cinnamon clown) is enjoying his new home.
I was checking out some sponges in the LR and noticed some new critters crawling around on the rock...I found a pic and they look just like this...

Are these guys good or bad? They're clear with white spots...rounded at the front and chevron tail....

 

[HClH2OFish]

BTW, that's not a pic from my tank....found it on another thread here but no identifier if it's good or bad...

 

[HClH2OFish]

LOL...NM on the ID....found it on Marc Levensons site...listed as benign

If you're interested, here's the link...

http://www.melevsreef.com/id/clear_flatworm.jpg

 

[DaisyPolyp]

That's a good site... I wish we had more people document their reefs that extensively