I don't have a dumerils but I have a nic and a red tail and they both have Cyprus mulch. And I must once a day or every other day but I have never had it get dusty on me tho. Mabey if u never most but my redtail likes to burrow so keep that in mind. A foot is fine for height.
1.0 normal bp- Blitz
1.0 Nicaraguan boa- Gavin
0.1 Red Tail Boa- Tara