TL Reefs Mushroom BoxUse this box for your mushrooms, anemones, or even fish acclimation. Hinged lid with pull knob Hole pattern designed to allow maximum flow while still maintaining structural integrity. Strong Neodymium magnets combined with a grippy oring hold the box securely in place on aquarium thicknesses up to 3 4" Magnets are completely encased in cell cast acrylic and will never get water in them. No worries about rusting magnets causing water quality issues.