I think it depends on the type of coco fiber.
Tons of people use Reptile Prime which is also a coconut fiber substrate and there are no issues. I personally have been using that and haven’t had a problem. That said, at pet stores, I have seen some coco fiber for sale in the reptile section that is suuuper finely ground almost like coffee grounds or soil.... maybe there might have been a report of an issue with that?
I’m sure your snake is fine - especially if it is acting in perfect health and temps and humidity are good. Don’t let them freak you out over nothing. On the flip side, there’s also no harm in switching to something thicker cut like a coco husk if you’re that worried about it. Peace of mind goes a long way sometimes.
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