Sizing Mouse Pointer

On AIX machines 4.3, 5.1, 5.2 and 5.3 am having trouble seeing the mouse pointer in CDE.
Found this on web
To change the cursor to a large red X, run the following command .

#xsetroot -cursor_name X-cursor -bg red

Could someone kindly give me the command line wording to undo the above command if it does not work out.
The man pages says to use -def to get back to the default values but not sure how to incorporate this in the above command line to reverse its effects.

Thanks

man xsetroot

Porter.
Many thanks for your reply.
Unable to sort out commands, as beyond my level of expertise.
Swapped from 17" screen to 21" which is a lot better.