Safe & Non-Toxic 5 Pound Bag of Gravel & Pebbles Decor for Freshwater & Saltwater Aquarium w/ Light Earthy Nature Tone Varied Texture Rustic Pond Creek Style [Brown, Tan, Orange, White & Black]

SIZE OF SUBSTRATE: Substrates vary widely in terms of size - everything from sands consisting of very tiny particles to larger river rocks. Large particle substrates allow more uneaten food and waste to penetrate into it leading to toxic build ups...