I would get rid of it.take it out, chop it down then You can put it in half a gallon of tank water with 3 cap full of peroxide for about 5min it should kill it over time.
It's not good. I have the same wire algae and it's spreading. I've heard this is a tough one to get rid of. I'm presently doing a Flucanazole treatment and added a pair of Emerald crabs yesterday. You're fortunate that it's only on the frags that can be removed and taken care of.