The Mechpia 13 Pieces Aquarium Decorations Kit is a complete fish tank setup that includes everything you need to get started with fishkeeping. This set includes a mini castle, four small plastic plants, a medium plastic plant, and a large plastic plant as well as a rockery with a hidden cave. All of these items are made from safe and washable resin materials that are free of harmful chemicals and will not affect the water quality in your tank. With this set, you’ll have all the necessary pieces to create a beautiful and unique aquarium environment for your fish.