Can a Tank be too Bright for Bettas?

[Nicci Lu]

It's growing, but very slowly. I think it has to do with something other than my filter flow, though, because I only got it to stop dying when I added other plants. At the time I first added it, the frogbit was my only plant. I had to increase my surface agitation a bit because I added otos to the tank, so if I'm not careful the frogbit zooms right to the outflow and gets sucked under. The only way I've gotten it to stay in one place is by using my floating hornwort as a sort of divider.