The coastal land in Puna is so new, that sand beaches are fairly unusual, especially near Kapoho. Instead the coast is a strand of Swiss-cheese mottled lava tide pools that are excellent for snorkeling. To reach the tidepools head south on Highway 137 at the intersection with Highway 132. Locally, Highway 137 is referred to frequently as "Red Road." The road was originally paved with the red cinders from the 1960 Kapoho lava flow. Now it's mostly patchy black pavement.
Turn makai just before the nine mile marker onto Kapoho Kai Drive and continue through the new housing area. Turn left onto Waiopae and follow it until you reach the end, park off the road near a sign that says "Reef Parking" After a short walk over lava rock toward the sea you will notice the pools. Many of the tidepools serve as swimming pools for the coastal homes, but the large ones are public access.
Please be respectful of the residents here and always take out what you take in. Make sure to bring reef shoes to avoid stubbed toes and try to get there at high tide or when the tide is coming in for the best experience. The pools are very popular with locals and families on the weekends and holidays, so shoot for weekdays.