I visit some dive sites with high expectations. Some meet these expectations. Other dive sites don’t have a big reputation, but they grow on me over time, eventually becoming one of my favorites. The Rock Quarry at Catalina Island falls into the latter category.

California Diving News
The Rock Quarry lies west of Long Point and Goat Harbor, but east of Sea Fan Grotto and Two Harbors. Because it is well protected, conditions are usually calm here. I like to divide this dive site up into three areas:  the shallow kelp, the rocky wall, and the deep sand.
Whenever I want good visibility, healthy kelp and prolific fish and macro life, I head to the Rock Quarry. Nowhere else in Catalina can I find so many different environments within a short swim, and such a good variety of marine life. Visibility can be excellent here.
There are a couple metal structures sitting on the shore, remnants from the old quarry that used to be here. Boats tend to anchor somewhat in front of these structures. The best diving is towards the left (east) side of the site.
To the left (east), the kelp forest is the nicest, full of garibaldi, opaleye, blacksmith, senoritas, perch, and kelpfish. Beautiful kelp canopies make great photo subjects when the light shines through. Continuing west at 20-30 foot depth takes you through a kelp forest as nice as any on the island. If you’re lucky, you may see a horn shark or leopard shark.
My favorite area is the rocky wall, which consists of large boulders starting at 30 feet and going down to past 60 feet. Ask the boat captain to point out where this wall is. Scythe butterfly fish, zebra gobies, morays, Hopkins rose nudibranchs, and rainbow scorpionfish make this area their home offering hours of great photo ops. All of the mentioned species are common here, but it takes time learning how to spot them; swim very slowly and carefully look into the boulders. Scythe butterfly fish are a distinctive yellow and black, and rainbow scorpionfish are more brightly colored than regular scorpionfish. There are also some nice sea fans at around 60 feet.
Last, but certainly not least is the deep sand. The east side of quarry gets deep quickly, and is a great place to look for angel sharks. Rockfish also hang out here along with juvenile treefish and an occasional nudibranch. Look for marine life where the rock and kelp meets the sand. You can get down to 100 feet without too much effort.
On my last rock quarry dive, I was just about to leave the wall and surface, when a large black sea bass swam right up to me, and stayed within 15 feet of me for at least 10 minutes. It never left my area.  I had to surface to avoid getting too low on air. Being not too far from black sea bass aggregation areas, sightings are fairly common here. Of course, I had my macro lens on, but the next time I dive the quarry I’ll keep my eye out for that hungry visitor–and take a wide-angle lens. 
Shearwater TERN