I have previously used Leo Sand on the Little Deeper, operating out of the Sea Mist Marina as Dive Charters International. His pitch is "you are only a stranger once on the Little Deeper", and he lives up to that. Nice, clean boat and a nice overall operation. Very mindful of ensuring 1-hour surface intervals between dives. Others also operate out of Sea Mist in what I would call a loosely aligned operation where they all share a shop and sign you up with someone else if they aren't going out that day.
Boynton Beach diving is almost all drift diving less than a mile or so offshore along a healthy and vibrant reef. As I recall, the top of the reef is at about 50 - 60 feet, and the bottom is between 70 and 90 feet, depending on whether you are on the blue-water side or the shore side. Leo drops off small groups (2 - 4 divers at a time), one of whom carries a float flag. When each diver hits their time or air limits, they follow the line back tot he surface where Leo comes and picks them up. When either of the last two hit their limits, they come up together. The person carrying the flag is "never lost", and the only job everyone has to do besides enjoy their dive is to keep track of where the guy is with the flag - easy to do.
You can reach Leo at (561) 734-3818, (888) 340-DIVE or firstname.lastname@example.org
. His website is www.deeper-dci.com