FWIW, there are no unbiased studies that have defined a particular tank size as minimum (or maximum). Anything the Betta Police aver is based strictly on opinion and we know what they say about those.
They're not delusional. They honestly believe what they preach because it's been preached to them and they believed the preachers. They anthropomorphize and use skewed human logic to support their opinions. "IMO" is not used often enough when discussing Betta.
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