Snorkeling at the Pier should definitely be done from the shore.
Enter the water on the South side where there are a set of cinder block steps. (you have to step over the chain fence). The entrance is rocky, so watch your step but once in the water, swim out close to the debris and rocks on your right. Lots of sea life, mostly smaller fish but there are a couple of big Puffer Fish hiding in the debris and for the past couple of weeks, the largest Blue Tang I have ever seen (dinner plate size).. when you get to the end you will find lots of Sweepers and smaller Yellow Tails. If you go right toward the Pier there are schools of Blue Tang.and the usual Sargent Majors. you can continue to the Pier and turn left and look for Sea Horses - about 5-6 rows out - bottom is 15 ft but Sea Horses are at abut 6-8 ft. it is a little deeper and dark under the Pier and viz can be less than ideal especially near the shore end
If you choose, you can turn left at the end of the rocks and head out to the "dolphins" (tie-ups for the old pier). Keep your eyes out on the bottom, there are Peacock Flounders and Rays in the sand. At the dolphin you can be pretty sure you will see at least 1 Turtle and be surrounded by schools of small Bar Jacks. Lots of life within the structure including Angle Fish and Trumpet Fish - plus all the usual suspects. Come back to the next dolphin, closer to the pier, and the coral growth is very good. Plus there have been small Butterfly fish and juvenile Angel Fish. Swim back along the rocks, to the entry point - watch for Cow Fish and the Puffers and small Trumpet Fish.
Part of the fun is watching the scuba divers near the bottom - sometimes they will stop to lock at something and if they do, explore that spot carefully.
Getting out takes some balance and timing with the small waves. There are a couple of rocks (depending on the tide) you can sit on to remove our fins.
The Pier is a great snorkel spot - as much as I enjoy diving at the Pier, the snorkeling is also very enjoyable.and we probably snorkel it as often as we dive it anymore.