You certainly can but with NZXT cases in particular be sure you are getting the correct sized upgrade fans. I have a Phantom 820 and just got new fans for it to upgrade when I upgrade my system to Skylake in a few months.
These are the fans that fit as the newer NZXT cases use true 200mm fans. As such not many 200mm fans will fit. They come in LED colors or non LED depending on what you want.