This may be a stupid question but here it goes anyway. Would it be okay to add a little sand in my Aphonopelma Chalcodes’s enclosure? I have it on a mix of coco fiber and vermiculite right now, with about 80 percent of that being coco fiber. I was wanting to add a thin layer of sand on a small portion of the enclosure. Maybe 25 to 30 percent of the space.