I want to make a substrate with vermiculite and sand. However, I don't find a small amount of sand to buy where I live. At the market I saw this white sand for aquariums. Does anyone know if I can use it to replace it?
That is silica sand (quartz) , if you want truckload quantities look up "Ottawa silica sand".Essentially typical beach sand without the few percent of iron oxides that give beach sand the "sand"color. It comes in many grit sizes , that looks pretty small , I would say too small ( packs too dense ) for aquarium plants. A quick look under silica sand shows many supplies for sand filters . Also , industrial sand blast supply will have the traditional brown color sand , usually called "garnet". It has been 20 years since I bought any ,probably $ 5 /50 lb. I did rinse dust out of the brown sand.