Glow Rocks Size: The glow stones are made of polyester resin. Each glow rock is approximately 2cm in size, and there are about 100 pieces in each pack. Glowing stones are available in various colors to meet your diverse needs. Glow in the Dark: Put fish tank rocks under lamplight or sunlight to absorb light for 2-3 hours then they will glow for hours in the darkness. and the longer their absorb to light, the brighter their glow and can be reusable. Various Uses: These glowing pebbles are ideal as fish tank rocks, aquarium gravel, fairy garden decorations, betta fish tank accessories, turtle tank accessories, outdoor rock decor for yards, walkways, as well as for filling vases, flowerpots, and plant gardens, making your home and yard incredibly beautiful. Ease of Cleaning: This glow fish tank rock has a smooth surface and doesn't contain debris. It's easy to clean, facilitating the quick daily cleaning of the aquarium. Moreover, the fish tank gravel create a calming ambiance in the tank, especially at night. The soft, glowing light mimics the natural moonlight, creating a serene environment where your fish can swim more freely and appear less stressed. This helps regulate their behavior and promotes a more natural habitat. Glow Stones for Indoor/Outdoor Use: Enhance your creative projects with these glowing gems, adding an eye-catching and enchanting element to paintings, sculptures, and DIY crafts; Illuminate pathways, flowerbeds, or water features with these stones to add an element of magic and wonder to your outdoor areas; Create a dreamy and cozy atmosphere in bedrooms, living rooms, or entertainment spaces by incorporating glow in the dark acrylic stones into your decor.