vidaXL Natural Red Volcanic Rocks - Ideal Aquarium Decoration and Natural Biological Filters, Suitable for Freshwater and Saltwater Tanks, Serve as Garden Landscaping Addition, Size 3-5cm, 10kg

【Biological Filtering】: Acting as natural bio-filters, these volcanic rocks foster beneficial bacteria growth, boost oxygen levels, and control nitrates, promoting cleaner and healthier habitats 【Attractive Decoration】: Their naturally occurring shapes make these lava rocks a visually pleasing addition to any fish tank or aquarium. The colour is an attractive red 【Size and Weight】: Each lava rock measures between 3-5cm, making them a suitable size for most fish tanks and aquariums. The total weight of the product is 10 kg 【Natural Material】: The volcanic rocks are 100% natural and entirely safe making no impact on your aquarium's pH or chemistry. Perfect for both freshwater and saltwater fish tanks 【Versatile Applications】: Apart from aquariums, these red volcanic rocks can also serve as an attractive addition to gardens, planter beds, and other types of landscaping rock applications