Answer: scubadive

AnswerCrossword Clue
SCUBADIVE

Visit the Andrea Doria, say

SCUBADIVE

Get in way over one's head?

SCUBADIVE

Go deep, in a way

SCUBADIVE
Explore with a tank
SCUBADIVE
Explore underwater
SCUBADIVEExplore a reef
SCUBADIVEExplore a coral reef, e.g.
SCUBADIVEExplore a big wet bottom?