WOAH....welcome to the site, but hold on there!
You need to slow down on stocking a CUC, because your tank won't support one and they'll starve out. You also really don't want to add the CUC while it's actively cycling as the spikes can kill them off. The idea is to balance your CUC with the needs of your tank, and temper it with the types of fish you're keeping (some will eat shrimp, for instance), so you can see that just stuffing a new tank willy-nilly with a large CUC isn't the best idea.
For a 55 gal, I wouldn't stock more than 6 hermits, and I'd only keep the scarlet reef hermits. Hermits are opportunistic omnivores, and if there isn't enuff algae, detritus, and leftover food, guess what's for dinner? Your snails, and once hermits develop a taste for snails, they will always be on the menu.
Stay away from Margarita snails unless you're keeping the tank at temperate temps (68*F max). Margaritas will die off pretty quickly at normal tropical temps, so they're a waste of money.
Also, hold off on the Turbo snails
unless you have a hair algae problem. They get huge (golf ball size) and are clumsy. In a 55, I'd go with 2 max if you need them. If you can find the Caribbean species with the orange shells, they are a MUCH better snail, and you can add up to 6 of them in a 55.
This is how I'd stock the CUC
INITIALLY until your tank develops a "personality":
SNAILS (6 each):
Nerite (try to find the species with tan shells with black carat (^) shaped markings...these are less "intertidal" than the black ones. Awesome for film algae.
Astrea general algae eaters
Trochus another good all-around algae eater.
Cerith (film agae, will clean at the substrate line). There are small, so you'll likely want to eventually keep 18 or so.
Also, you'll want a couple of Nasasarius snails to start...eventually get 6 for a 55.
You can toss 6 peppermint shrimp in the mix as well.
Give this article a read before you buy anything...it's a good primer on choosing a CUC:
http://www.lionfishlair.com/cuc/cuc.shtml
Sorry for the lengthy post, but this is one subject on which I have a pretty strong opinion...