Aquarium Substrate | Grey - 1/4 to 1/2 inch

Our substrate is 100% real slate stone that is sourced, sorted, washed and packaged in the USA by our family owned business.  Each box is a mix of gravel from 1/4" to 1/2" (some stones may be slightly above or below this range).  Absolutely no coatings on this or any of our stones.  An excellent gravel for Aquascaping aquariums or use it as a topper for soil in a planted tank.  The grey/blue color makes wood, plants and other inhabitants  and decorations pop. Pairs perfectly with our Natural Slate Stones that come in sizes from 1 inch up to 10 inches for a cohesive, natural scene. Perfect scale for miniature models and scenes as well as a topper for succulents and other potted plants. This substrate is a beautiful, deep grey matte color, with a hint of blue.  Because this is a natural stone, some white quartz or brown stones may be mixed in that add to the natural look.  Some of the quartz pieces may have a small amount of calcium.  We have not found this to alter water para