A dive on Navy Pier is always spectacular. SIngle or double dives depending on the tides are on offer with Whaleshark 'n Dive. I went yesterday with my son and saw large schools of trevally, barracuda, dozens of big cod, lion fish and my favourites...sharks......Read Full Report
There is a great dive site that isn't often visited called Simon's Reef.
It is a bunch of massive bommies (coral mountains) that form a valley over the white sand.
This site is excellent for doing the deep diving speciality as you can go down to 40m and kneel on the sand with coral all around you. Very cool.