FCPX doesn't have a white balance filter, which on the SI scale of inexplicable counts as about five Marie Celestes. Sure, you can fiddle with the colour board, waggle some pucks around like you know what you're doing, bitch about how much easier it would be if they'd only used three colour wheels because, dammit, you were familiar with waggling those around like you knew what you were doing and you shouldn't have to learn this whole new way of waggling, FFS.
Yeah, or: you can drop a few bucks on one of the squillionity of white balance plugins out there. Which is cheaper than the time you just spent bitching about the colour board, right?
Ah, but which one to choose? There are so many.
I've used a couple of these, haven't tried them all, but my favourite so far? Nick Dashwood's in his Editor Essentials pack for FxFactory. For $49 it comes packaged with a dead pixel fixer, anamorphic reverse de-mungers of every stripe, quick gamma curve correction, and... wait for it...
...a preset for 'minus green.'
What, you're telling me you always wrap every practical fluo tube in minus green gel ahead of every shoot? T'ch yeah, right. Oh, you have a bridge for sale? Sure I'm interested. Let me finish this post first, m'kay?
Right, so making people look less like aliens from the planet Queasy is one of those things we do every.single.damned.day, but lining things up on that itty-bitty skin vector is quality time when you could be down the bar. Deity Dashwood brings a preset that, on my footage, nails it. Hard.
Mind you, Jonathan Richards is a nice guy too and his HyColo(u)r plugin has a green caste removal checkbox. Dammit, choices! How am I supposed to get any work done? I'm done with FCPX, I'm jumping ship for Premiere Pro!
What's that? Premiere doesn't have a minus green tool by default either?
Pour me that damned drink, I'm gonna explore Lightworks.
Leave the bottle.