Substrate: Many newcomers use an inert and/or non-nutritive substrate such as gravel, pebbles, rubble, or sand in their tank.
Substrate: Many newcomers use an inert and/or non-nutritive substrate such as gravel, pebbles, rubble, or sand in their tank. The type used will affect what you can and cannot plant—or whether you can plant in the substrate at all. A key point is grain size.