Just a question, so are you saying they don't take in oxygen from the water as well? Cause from my understanding this adaptation allows them to live in very low oxygenated waters, but not water completely lacking oxygen, all other factors accounted for in this situation for the question. Just looking to learn.Bichirs breath atmospheric oxygen... oxygen content in the water doesn't matter.
To each their own, but your overthinking it. The holes will just make a mess. They will be fine in a normal bin with enough space for them to breach.