The ZooMed AquaLog Sinking Fish Shelter is an innovative aquarium decor that provides a naturalistic refuge for fish of all sizes in both freshwater and saltwater environments. Crafted from eco-friendly plant resin, this shelter not only enhances the aesthetic appeal of your tank but also promotes beneficial algae growth, contributing to a healthier ecosystem. Its large size at 12 inches x extra-large makes it suitable for various fish species that appreciate spacious hiding spots.