Just far enough away from Makassar to shed most (but not all) of the rubbish, the white sands of Pulau Samalona are popular with day trippers, particularly on weekends. There are patches of (degraded) coral offshore, some reef fish, and snorkelling gear for hire. Compared to Makassar harbour, the water’s pretty clear. Cold drinks (including beer) and fresh fish are available, but bring your own water. It takes a full two minutes to walk around the entire island.
Boat charters for up to eight people (return 400,000Rp, 25 minutes one-way) can be found at the various peers along the Makassar waterfront.