Aquatic Arts 4 Cholla Wood Pieces - Sinkable Aquarium Driftwood/Dried Cactus Branches - Natural Hollow Decorations - Fish Tank/Terrarium Decor REAL CHOLLA CACTUS WOOD: Bundle of 4 large pieces, each at least 5 inches in length. Natural sinking decoration for aquariums / creative mount display / DIY crafts. DRIED AND CLEAN: Thorn-free, chemical-free, sinkable, and ready for tank use out of the box. You can also boil the wood to remove excess tannins first. NATURAL WATER TREATMENT: Produces ideal water conditions for acidic loving animals. Lowers and buffers pH; perfect for lowering pH gently and naturally. HOME DECORATION: Creative decorative ideas including: air plant holder, wall mounted ornament, hanging centerpiece, succulent planter accents. TANK / TERRARIUM USE: Great for anchoring moss and planting plant buds. Provides a hiding place for small freshwater animals, a trunk for a bird to perch, or a sheltered log cove for a pet reptile.