Hi all! First time poster here. I had a quick question about an outdoor enclosure. My 1 year old sulcata is right at a little over 5 inches in length and 500g. I am looking to moving him outside at least part time through the day (I live in Phoenix so there is relatively nice weather year around except for hot summers)I am planning on using the space outside of my house with pictures attached below. Right now it is fully concrete or pavers at the bottom. I am planning on stacking some pavers higher around the enclosure to give added height and will build an enclosed area for heating. What I wanted to know is what type of substrate should I put down at the base of this? Orchid bark or cover it with soil and sod? Any help would be appreciated.