I like the general idea of a bioactive enclosure, but i'm not a fan of how that video does it, too small .I dont have a hermit crab but you should look at bioactive enclosures!
Ilove CCS! Their whole account is wonderful, and they really helped me get on track with my care. Went from a 5gal with awful care, to now a 45gal with proper care. Thhey're awesomeIf you're on tiktok and youtube, I highly recommend the page CrabCentralStation! They have several hundreds of gallons in total of space for their hermies!