Quote Originally Posted by hungba View Post
I have kept and bred BTS of various kinds for some years.
They do dig sometimes but is not necessary to let the have so much soil that they can actually burrow. Mine are given only about two inches of substrate and they are content to dig in that and feel safe inside their hides as long as the entrance of the hide is small.

I wouldn't use soil, as in the long run it is much more trouble than it is worth. The substrate of choice for my Northern BTS is this product called aspen supreme, which are pelletized aspen. They break down to "dust" when wetted and thus pose low (not no) risk of impaction (as long as you don't just let them eat lots of it regularly or throw food on it without a plate etc.) The "dust" isn't fine like sand and is coarse enough to have weight and not be dusty. The only disadvantages is that it is 1) the color is brown and sometimes feces is hard to spot, and 2) because it disintegrates when wet, they do require more changing out than some other substrates.

Recently, I have also started using another product called KOMODO straw terrain. It is olive green in color and you can spot feces from across the room. Also, they break down to similarly coarse "dust" when disintegrated, but not as readily and lasts longer than the aspen supreme. I had used other brands of straw pellets before from a company that now discontinued it, and the aspen supreme was sold out for a while, hence my posts looking for alternate substrates recently. The old straw would form mold under the bowls, but this Komodo straw really doesn't seem to mold at all, living up to it's claim on the packaging. I am very happy with it so far. I also found birch pellets which I purchased but have not tried yet.

For indo species I do not recommend these substrates, but since you're asking about northerns, that's another story.

Can I ask why you would say that soil is more trouble than it is worth and that a deep layer isn't needed? Soil when done properly is almost zero upkeep, on another note while 6 inches of substrate isn't "required" it isn't a bad idea either.