Will RO dip kill Eunice worm?

[Kewlworm]

I have a zoa colony rock that losing polyps slowly. I found a tiny one the other day when I was fragging it (for just in case if the colony was sick.) It is about an inch long.

I am planning to do a RO dip...how long should I leave it in there to kill the worms and not the zoas? How many time should repeat doing it?

Thanks in advance!