Banana trunks ( Musa spp. ) are used in terrariums and aquariums for their beneficial properties. In terrariums, they provide natural support for climbing plants and help maintain moisture in the soil. They also provide hiding places for small animals and insects. In aquariums, banana trunks release tannins, which can help acidify the water and promote the development of biofilms. Their slow decomposition also enriches the substrate, creating a healthy and natural environment for aquatic and terrestrial organisms.