Keedolla 3 LB Aquarium Glass Pebbles Decor Rocks for Fish Tank, Crystal Betta Fish Tank Rocks Gravel Gemstone Beads Vase Fillers Decorative Mosaic Glass Gem Pebbles - AmberHow to Choice: Small crystal stones is 6 9mm (0. 25 0. 35), 0. 93LB Pack, about 0. 3 liter capacity. For example, if your tank size is 6. 3* 6. 3", it will needed 1 bags for about 0. 4 of depth Features: The glass gemstone is like river gravels, no dye or other methods of artificial coloring is used, never faded. Smooth edges no harm to animals and plants, you can rest assured that using. NB the glass pebbles are 0. 93LB Heavy Enough BUT SMALL BAG