You can use distilled water to mist the enclosure while avoiding the frog; but not on the frog's dish. For dish I only recommend dechlorinated (Seachem Prime or ExoTerra Aquatize) tap.

ABG type soil mix can replace the shredded coco. The soil should be prepared with dechlorinated tap too and replaced monthly unless it's ABG soil with natural plants and an established colony of springtails and other detritus feeders.