I gave Reggie a dig box a few weeks ago, and hes loved it. I'm now wanting to do a third or a half of his enclosure with loose substrate. I used australian desert sand for the substrate but thats too expensive to keep using. I want to do a 50/50 mix of play sand and top soil. Are there any specific brands people usually use, or things i should look out for? Will I need to wash anything/mist the substrate at all?