Along of Cancun Coastline or crossing to Isla Mujeres and around  there are many places to stop and swim and snorkel , On same day Captain and you choice better places by wind conditions

check pictures: http://www.mexicotravelshop.com/what-we-can-do-on-yacht-at-cancun-isla-mujeres/

You can stop at a place of Cancun where you can rent waverunner or another toys and pay only for use of it,  you do any of them from yacht while all the group enjoy aboard or jump to water

We have options of Fly board/ Wave runner / banana-boat / parachute and more