Friend or foe? Never seen'em before- what are they?

[mevstheworld]

The v'd tail on them smaller guys tells me its a flatworm. Most likely nothing to worry about.

They look exactly like red planaria, NOT GOOD!!! They can become so invasive the will cover glass, corals, etc. They don't hurt anything, but will bleach out corals by covering them and stealing their light. They can become plague like. They split to reproduce. +1 on the coris or sixline wrasse. If you treat for them make sure you siphon as many out as possible several days in advance to minimize die off which can and will nuke your tank. They release toxins when they die. Hope this helps http://www.melevsreef.com/flatworms.html


Good luck!

 

[aquarius77]

They look like benign flatworms to me, ive had red planaira in the past and i have benign flatworms in my sump now. The harmless ones are clearish tan, both are on the id page just linked.

 

[xrayrider]

There is a type of nudibranc that will totally eradicate them. I believe it is called a velvet nudi, and it has a bright glowing blue stripe on it. It can get into the small places, to get the ones the fish can't reach. They are hard to come by, but you can probably find some somewhere online, They will starve to death once the problem is resolved. It is good to pass them around, from one friends tank to another, so they don't starve to death. They will totally eliminate all the flatworms, without any risk of toxins being released, and without adding chemicals to you system, which something I always try to avoid, if possible. They have a ravanous appitite.