• Made of Natural Materials
• Easy to Use 
• Adds Essential Minerals to Aquarium Water

These shells are great for adding hardness and minerals into your aquarium water. If you need more minerals for snails, shrimp, plants, goldfish or African cichlids etc, Wonder Shells are a good place to start. They are extremely easy, just drop it in your aquarium. Over time, Wonder Shells will completely dissolve into your water. Simply replace them when they do.