I would please reconsider this stocking option. Currently you are at 150+% and you would have to do a 50% water change a week. Which would stress any fish out, let alone a betta sorority (which can be finicky on its own) as well as neon tetras, and the otos. I would seriously think about a new stocking options. If your going to do 8 females, just do females. I would also just subtract the otos from the equation altogether.
"I am not afraid, I was born to do this." -Joan of Arc
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