Flat worm extermination

[Michelesreef]

How apparently i have flat worms and if I'm not wrong, they're just a small as copepods if not a little bigger.....right?
I have a TON of copepods in my nano tank which only houses 2 nass snails and a few different corals. This whole time i thought those were just adolescent copepods but if not...what do i need to do to get rid of them??
Do they hurt my corals??
Once i get home i will take a picture of my flower pot(?) Polyps (they look like daisies) and post it because the head of one of the polyps is just completely missing....did a flatworm do that?

 

[Old Fritz]

Here's an article on flatworms

Tl;Dr version
Some flatworms are harmless, some aren't. If you post a picture we can give you an idea of what it is.
It can be harmful to corals depending on species
You can get rid of them with fish like the melanarus wrasse or six line wrasse.
It can also be removed with flatworm exit by salifert.