zoa eating nudi's

[cuz]

only because of the availability of the yellow coris here in town i was planning on a 6-line wrasse tomorrow.
thanks for the help Levi!!
I have had 2 zoa colonies dissolve down to nothing but thats been over the course of 1 1/2 yrs so i ruled out nudis previously. Now its got me woundering!!

what is the differences between zoas and palys in a nudis eyes? as quoted above? keeping palys as a pro-active measure??