Some copper is better then others not as harsh on scale less fish.
what kind are you thinking about using?
Be aware that copper is lethal to all your critters like pods and you will most likly not be able to house inverts in the tank again.
240 is a large tank and I am sure you want lots of diversity, but copper can leach into a lot of stuff like your silicone.. I would think twice before doing it.
Are you thinking you have ich?