Virgin Cork Bark Tubes - 1 Pound (1-2PCS) - Amphibians, Reptiles, Bromeliads and Terrariums

I plan to make a bioactive paladarium but do not know if these will fit around my planned filter. I plant to use the zoo med paludarium filter.

I’m confused it says tubes on the main pic but when you read the description it says flats? I’m looking for tube.

Would these work In a high humidity enclosure?

How long are these