Zeke.
I'm a DM, dive 95% of the time in the Durban area and live in a small holiday town 30 minutes north of Durban. (Ballito).
You're coming to the right spot! Especially in May when the vis is slightly better and fortunately for us, it's never really that cold in our water. Expect around 18 degrees in May on average, but anywhere from 16 to 21, depending on what the wind has done to the currents. I dive an old worn 5mm all through winter and summer.
For sharks, you're going to want to go to Aliwal Shoal. It's a marine protected area with some excellent diving and there are fantastic operators in the area, some of them dedicated to baited shark dives. Typically on a non-baited dive in Aliwal in May, you can expect to see raggies, and sometimes blacktips, anything else is just good luck. The two operators I recommend are either ScubaXcursion or African Watersports. ScubaX are just great people with a relaxed vibe while Walter at African Watersports is the Shoal's local shark whisperer. I'm not kidding, you should see him tickle a tiger until it "falls asleep".
Sodwana (about 3.5 hours north of Durban) is the best diving in South Africa. You're less likely to see sharks there, the vis will be better and the water warmer. I love it and in fact went up there with a huge crowd in December last year to celebrate my 40th. Personally, I recommend Coral Divers for their relaxed, but very very organised operation.
Ponto is about 4.5 hours north of Durban (through the border into Mozambique). Excellent tropical diving, calm, warm, flat seas. It really is great and May is a good time of year too.
In Durban itself there's only really one operator to speak of and that is Umhlanga Scuba. Excellent operation. The owner is a rebreather diver, tech instructor etc. In fact, I'm busy doing my tech course with him at the moment. Our local club uses him for most of our dives and if you're on a Saturday morning dive you can expect half the boat to be filled with regulars (including me) who know each other well, talk ****, laugh and have a great time. Often you'll find that more than 50% of the boat is made of of DMs too. Another point to note is that when conditions aren't terrible, we do a night launch at least once a week.
I'm guessing your wedding is in the Midlands area (Pietermaritzburg, Howick area?). With your itinerary, I would do the wedding, head to Aliwal for 2 or 3 days' diving. Drive an hour to Durban, do 2/3 days diving, drive to Sodwana for 3 days and then spend the rest of the time in Ponto. 4/5 hours drive back to the airport.
Some things to note:
No liveaboards in the area.
Notable wrecks are the Nebo and Produce in Aliwal. (Both great, expect a decent current on the Nebo). T-Barge, Fontao and Coopers in Durban. My favourite 3 local sites. (Coopers will blow you away on every dive, the only problem is that sometimes it's the current that's blowing you away and sometimes it's the conditions
)
Durban is not known for visibility. Typical is around 8m to 10m, but I've had 30m and a fair share of 1m to 2m. Both Aliwal and Sodwana typically have better vis. In Durban, it's all about the wind. When the east blows, you know you're going to need to feel your way around the dive.
Everywhere we've discussed above, you'll dive from a RIB. That's OPS normal here in South Africa. Expect a beach launch through the surf. It's really not as rough as some might think & typically ladies are on the boat early while the chaps help push it out and jump up.
Lastly, Durban has a fleet of deeper wrecks, but don't plan a quick visit to a 75m wreck, no operator is going to do that without "getting to know you" first.
Feel free to ask anything else you need to. I hope you have an awesome trip & we see each other on the boat.
