Aquarium Sand Types

A substrate is a vital part of an aquarium. This is what lays on the bottom and provides not only the "floor" of your aquarium but also provides growing space for beneficial bacteria. Sand is a common choice in aquariums, but new keepers may be intimidated by the many varieties of aquarium sands available. Each type of aquarium sand brings with it a benefit that may make it ideal for you.

  1. Play Sand

    • Play sand is very common and affordable. It consists of medium-sized sand grains as well as dark, tan-colored clay, giving it a very natural look but also making it somewhat messy. It can cloud an aquarium if fish dig in it and may take several hours to several days to settle.

    Black Beauty

    • Black Beauty is not actually sand, but a type of iron slag used for sand blasting projects and sold in hardware stores. The sand is very affordable and is available inexpensively in large quantities, but it can be sharp and cut fish that enjoy burrowing.

    Silica Sand

    • Silica sand is one of the most common and is tan colored and often uniform, with medium-sized silica sand grains. It is available in sacks of 100 lbs. or more, making it ideal for large aquariums. It's also very clean, making it an ideal choice for beginners.

    Crushed Coral

    • Crushed coral sand is a type of substrate made from the crushed remains of dead coral. The crushed coral brings a nice, natural aesthetic to an aquarium. It naturally raises the pH of aquariums when added to the water, making it an ideal choice for high-pH environments like those in marine or reef aquariums.

    Aragonite Sand

    • You should only use aragonite sand, like crushed coral, in marine aquariums because it raises the pH levels substantially. Aragonite is a calcium carbonate mineral often found on the sea floor. It constantly releases calcium carbonate into your tank, which gradually raises the pH. You can mix it with the crushed coral sand in saltwater aquariums to better maintain the high pH.