I'd go with the nerites and florida ceriths. I'd skip the dwarfs if they are going in anything over 10 gallons. I like astrea snails too. More hermits just means more snails eaten. I use cleaner shrimp for finding uneaten food in the rocks and nassarius snails will get the stuff in the sand. I also keep a fighting conch. He is slows but he cleaned my substrate in a major way. One is all I needed in a 58g