Shop / Litter & Accessories / Estes Spectrastone Permaglo Pink Gravel Estes Estes Spectrastone Permaglo Pink Gravel Weight: 5 lb $18.99 Sorry, this product is currently out of stock. Information Ingredients Spectrastone Permaglo pink is an ideal substrate for fresh water and marine tanks. Our Permaglo colors use silica quartz which is an inert stone that will not affect pH. N/A Customers also liked Customer Reviews