How heaps woman bettas can my reservoir enjoy?

ok- i have a 20gal long heavily planted fish tank. It currently contains:
4 tiny von rio tetras
2 female bettas
i found this exquisite male betta and I want to add him in nearby
i think the plants and the abundance of hiding areas will keep anyone from war, but do you think i could add maybe another womanly? If they ever do mate, should i take the other ladies or the male out of the tank?
Two female betta should be fine. I would vote though that the more betta you have the more likely it is that two of them might not get along and skirmish. Females are not as likely to fight as males are but are definitely specified to do it if each fish doesn't have adequate room to mark her territory away from the other betta.
Adding a male is out of the question--males and females WILL fight if kept together, no concern how heavily planted the tank is. 2 females is also a bad idea--you want a group of at least 6 so they can form a heirarchy and spread out aggression. You could slickly add 4-5 more females, and doing so would be a good idea. But again, do NOT put a masculine in there!
Answers:    You can give another female and the male,but, be warned, when the masculine sees that there are females in the nouns he will start building a bubble nest. Any fish that comes within site of this nest will be aggressively chased away including the females if they aren't arranged to mate. You can tell when they are ready when you see a tiny white bead in front of their anal fin and their stomach looks full. Feeding them a good balanced diet on a regular basis will seize them ready to breed. The male will tend to the fry and chase any intruders away. As long as your container is as you say heavely planted you shouldn't need to worry nearly removing any of the fish.
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