Need help on building a 10 gallon background using clay

[kev48584]

so i want to make a horizontal vivarium using clay but i'm not sure what kind of clay i'll need and how much i'll need for a 10 gallon. i plan on keeping a poison dart frog with high humidity in the enclosure if that helps. i've seen people use kitty litter but it doesn't appeal to my eyes

[deranged chipmunk]

i've only made clay backgrounds from kitty litter that i tinted with acrylic paint to get the brown, muddy look. i think the clay that was used a lot was a masonry clay? but i am not 100% sure on that.