Is there anything I should be adding to bedding to lower the risk of mites, bugs ect...? I use pine shavings and change it out once a week but is there something I should or could add to lengthen the life of the bedding? And or improve their health, they have a 60 sq ft run but not much dry dirt. so i'm also worried about them dust bathing in the shavings as I see them do it already...