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Growstone GS-1 Hydroponic Substrate 1.5cuft






Growstones are a new hydroponic media created by pulverizing and baking recycled glass with natural additives. Growstone GS-1 is designed to be used in all hydroponic systems and can replace many other mediums like Rockwool, expanded clay, and perlite. Growstones create an effective balance between air and water content, providing plants with all the water they need to grow but also quickly draining and aerating roots when water is withheld. There are countless varieties of hydroponic substrates on the market, but Growstone is the only patented medium with proven field results.

  • Highly effective balance between air and water content at field capacity, meaning high air-filled porosity coexist with high water holding capacity.
  • Growstones hold 3 times more water and 12% more air than expanded clay.
  • Size: 1.5 cubic feet

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Growstone GS-1

Engineered specifically for hydroponic use, Growstone GS-1 provides growers with an ideal blend of water-retention, porosity, and drainage for growing media use. Growstone’s patented manufacturing process has created a material that holds 3 times as much water and 12% more air than Hydroton. Lightweight and durable Growstones will last through thousands of drain and re-wetting cycles and can be reused for years, unlike many other mediums which degrade over time. Growstone GS-1 sets an industry standard for powerful and sustainable growing media, pick up a bag today and grow the difference yourself.

How it’s Made

Growstones start their lives not as rocks, but as recycled glass bottles. The glass bottles are collected and then pulverized into an ultra-fine glass powder, about as fine as baking flour. Natural foaming agents and additives are mixed in at specific ratios, and the whole mixture is then fed to a massive kiln to bake. As the mixture is heated, gasses are forced to escape, causing the material to rise and forming it’s highly porous and air-filled structure. Once finished baking, the Growstones are cooled and crushed into pieces for packaging.

Growstone: The Sustainable Choice

Growstones are manufactured using up to 98% waste materials. They replace mined materials like pumice, perlite, clay pellets, and stonewool, reducing environmental degradation. At the same time, since the product consists overwhelmingly of recycled glass bottles, a large amount of glass waste is given a new life, keeping it from the landfill.


Weight 5 lbs


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