Keep in mind that Moss species is from North America and likes a lot of light. If it survives in a tropical tank pls let me know I'll buy some!
With respect to what you've found on internet forums regarding Hornwort, an old adage comes to mind:
"Don't believe anything you've heard or read, and only half of what you see". [emoji12].
(and yes that applies to this forum as well, although there are fish keepers around here with 50 years experience in keeping Betta).
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