Hi I'm new to this and haven't had my tiger salamander very long I found him outside and fell in love but Oscar doesn't burrow at all I've tried just moss in his aquarium and just terrarium soil and I've also tried mixing them I was just wondering if its because the substrate is to moist or dry or if I could be doing anything else that is preventing him from burrowing I want him to be happy and if there's anything I'm doing wrong I would like to fix it thank you for your time and hopefully someone can help me