Aquatic Arts Deluxe Nerite Snail Combo Pack (Neritina natalensis) - 1 Zebra, 1 Tiger, 1 Black Racer, 1 Sun Thorn, 1 Tiger Eye, 1 Zebra Thorn Nerite Snail - Live Snails These are nerite snails, so they absolutely never reproduce in freshwater - great for aquarium hobbyists who don't want snails reproducing in their tanks! Nerite snails are widely known as one of, if not the most, voracious algae-eaters out of any snail. Tiger, Zebra, Black Racer, and Tiger Eye nerite snails usually range from 1/2 to 1 inch in diameter, while Sun Thorn and Zebra Thorn nerites range from 1/4 to 1/2 inch. Each type of nerite snail's shells are diverse and totally unique! All Aquatic ArtsTM (formerly InvertObsessionTM) brand plants and animals come with a 100% live arrival guarantee, plus free email support directly from the owners!