BLUE TONGUE SKINKS

So Plinko has been great, totally normal, healthy, eating, etc...

but today I found a small poop that had maybe 3 or 4 chunks of aspen in it. To be honest, it just seemed like the aspen was encased in the poop, the poop was mostly aspen. It was a small poop, definitely not one of his normal big poops.

Plinko's been so good about not eating the substrate I kind of stopped watching him, but now I'm a little concerned. I've never found aspen in his poop before.

Advice? Should I switch substrates? should I feed outside of his enclosure? I've never seen him eating the substrate on his own but now i'm a little worried he might be doing that. At least he passed it...?

Start feeding outside the enclosure. That is what I do. Some take out the Aspen through-in-through, but to me substrate>hides and my skinkers feel the same way. I wouldn't take out the substrate.