oneshot,
Are they in the same pot or separate? If separate, are the roots seriously intertwined?
If the roots aren't seriously intertwined, pull them both out of the DWC, put the female into PHed water, discard the male, drain and THOROUGHLY CLEAN THE REZ AND ANY CIRCULATING SYSTEM YOU MAY HAVE.
At this point refill the rez with new nute solution and reinsert the female and go on like normal. You will not be in any worse situation than if you had just moved them from one rez to another.
On the other hand if the roots are seriously intertwined or they are in the same pot, you probably will loose the mother too if you try to remove the male. It just depends on how much damage you do to the roots of the lady while you are removing the male.
It is possible -- but highly unlikely -- that you could just cut the male without messing with intertwined roots, but I would highly doubt it. If the roots are seriously intertwined, I'm afraid you're pretty much screwed. One ting you could do if you are trying to keep the female because of its genetics is to clone it and then do whatever you have to do about the male. In fact that would be my recommendation any way is to clone the female immediately and then do what ever you have to do about the male/female cohabitation problem you have.
Good smoking.
