help nudi invasion

[prodogg02]

hi i just got a zoo coral frag on thursday from a good store here today i noticed its not open looked at it and its covered in little grayish nudibranches (i think) they are small the biggest one i crushed about quarter inch long should i nuke the frag hate to do that how do i get rid of them are they gonna eat my zoos no experiance with these theres about 10 i seen on a golf ball sized frag never seen them before figure they where hicthn a ride.thanks for any info