i use sand for all my monitors,never had health issues,id have to wonder why people are against it,but everyone has there own opinions,i use what im happy with,i must say though that with my mertons,i used sand for the first 18 months,but with there going in and out of the water,all the sand ends up in there pond,lol,so now i use sugar cane mulch,and am very happy with it,barely any gets in the water,i also use it for my lace monitors to,easyer to clean out there cage,and more natural than a sand substrate,to the non sand users,may i ask what u would use for monitor nesting?