Snorkeling in the Aitutaki Lagoon.
Neil Mitchell's Aitutaki Scuba offers diving at the drop-off once or twice a day (except Sunday). If you have your own equipment, diving is a bit cheaper. Snorkelers are welcome to go along when space is available. No reservations are required, but bring your own mask; wetsuits are handy June-December. The diving here is better March-November. Aitutaki is good place to learn to dive and Neil does four-day PADI certification courses (minimum of two people). You'll find Neil about a hundred meters down the side road that branches off the main road at Amuri. Aitutaki is not an easy dive destination. The lagoon may be great for snorkeling, but it's too shallow for serious diving and the drop-off outside the reef is very steep (not for beginners).
Scuba diving is also offered by Onu Hewett of Bubbles Below on the hill above the wharf in Arutanga.
Aitutaki Sea Charters offers deep-sea fishing off the 10-meter cruiser Foxy Lady. Captain Jason and his father, Don Watts, live near the Crusher Bar toward the airport. Skipjack tuna, giant trevally, mahimahi, and barracuda are caught year-round off Aitutaki. The billfish (marlin) season is November-March, while in August and September wahoo are frequently caught.
The Aitutaki Golf Club beside the airport welcomes visitors. Greens fees and club rentals are reasonable. If your ball falls on the airstrip, it's considered out of bounds. The Aitutaki Open Golf Tournament is in mid-October.