I actually dove a site just a couple hundred feet south of the Puako Church, but it is essentially the same area. This is turtle sanctuary and one can study these fascinating creatures sunning themselves on the lava or as they swim effortless in 20 - 60 feet of water. The entry along here and in many Northern Big Island sites can be a challenge, especially at low tide. The lava is rough on feet, footwear and gear. It is usually better to dive at high tide - but always be careful of urchins if you use skin-diving fins. Another entry challenge can be wind driven surge, though it isn't as difficult as other Hawaii sites. The swim to 40' depth is about 300 meters at high tide - I would suggest that seasoned divers put their snorkels back on and use them on the surface swim there's much to see and it will make swimming through the surge easier. Once at the 20 - 40' levels, just drop down and swim among the lava tubes that have become healthy coral walls. The yellow tang, wrasses, butterflies, other common Hawaii reef fish are prolific here - ostensibly beyond the reach of collectors in this protected area. The turtles are tolerant of divers who don't present themselves aggressively. Morays are also friendly to those divers who keep a non-threatening distance.