Good substrate for dig box?

[MadMeeper]

Hello! I have two beardies currently, each in their own enclosures. Sandi, my big gal, is about 13-14 currently and Tiger, my little runt boy, is about 12-13! I've had these guys since I was a kiddo, and as a result of just what was standard keeping back then, they lived on sand for about 12 years. Thankfully they didn't develop any nasty side effects from it because I was very careful, but they live on tiles now. I did notice, though, that they miss digging!!

So the question is, what's some good, safe substrate to give these guys that they can dig in? Preferably I don't want something that smells, they live in my room and Tiger is housed on my desk.

I do not breed them and I have no plans to! I'm just trying to find new enrichment methods that don't require me to be home since I'm a full time student and am away from home a lot. It's the summer though which means I have the time to do enclosure modification!

 

[CooperDragon]

I like to put down scraps of fleece over part of the tile. It's easy to clean and allows for some digging/burrowing. If you want a more traditional, separate dig box then most folks use a combination of moist play sand and organic topsoil because it will hold a tunnel structure. It gets pretty messy though.

 

[BadCon]

I've used alfalfa pellets as dig box material, but be warned it will get EVERYWHERE.