Speaking with some experience, betta breeding would be next to impossible in a community tank. Bettas are labrynth fishes, which means they have a special organ in them that allows them to take oxygen from the air. They are also very aggressive when not mating. Females can be kept together when they can hide from one another, but if you keep a male in the tank, the females will constantly harass him. Either they will bully him and shred his fins, or they might try breeding with him, but once he has eggs and fry up in his bubble nest, he will kill ANY female and any fish that comes near it!!
As if that isn't bad enough, the bubble nest requires almost stagnant-still water to keep it's surface tension constantly when harboring the super-delicate betta fry. The male will maintain the nest, cleaning it, adding more bubbles, and keeping his brood suspended in the nest. Any ripple or vibration would cause many eggs/fry to tumble helplessly from the bubbles and the male would literally exhaust himself trying to keep them all contained in his nest.
Once they are free-swimming out of the bubble nest, the male (who would've been their caretaker until now) must be removed or he may start eating his own young. Their labrynth organs are so fragile for the first two months that even a cool breeze over the water surface (their source of oxygen) could wipe them out!!! So when I was breeding them, I had to keep saran wrap over the top of the aquarium and I could use no filtration at all until they were 3 weeks old. Also, the water can't be more than 4 inches deep. Anything deeper and they exhaust themselves rising from feeding at the bottom to get air from the top. Yes, the baby fry can literally DROWN! Then, when they are so tiny, they require zooplankton to feed on and then they eat baby brine shrimp after that. That gives you an idea of how tiny they are and how easily everything else (female bettas and occasionally even MALE betta included) would consider them a fine snack.
The most filtration you can give betta fry until they are roughly 1 inch long is very gentle... submersible sponge filtration is suggested. They swim very slowly and easily get slurped into anything stronger than that. So as you can see, the best way to breed bettas is to separate a single pair into a 10 gallon with 4 inches of water (I suggest adding a teaspoon of blackwater extract to condition it) and go from there. It'd be a disaster to breed them in a large communal tank and some or all of your bettas would end up damaged or killed trying to mate in there.
As if that isn't bad enough, the bubble nest requires almost stagnant-still water to keep it's surface tension constantly when harboring the super-delicate betta fry. The male will maintain the nest, cleaning it, adding more bubbles, and keeping his brood suspended in the nest. Any ripple or vibration would cause many eggs/fry to tumble helplessly from the bubbles and the male would literally exhaust himself trying to keep them all contained in his nest.
Once they are free-swimming out of the bubble nest, the male (who would've been their caretaker until now) must be removed or he may start eating his own young. Their labrynth organs are so fragile for the first two months that even a cool breeze over the water surface (their source of oxygen) could wipe them out!!! So when I was breeding them, I had to keep saran wrap over the top of the aquarium and I could use no filtration at all until they were 3 weeks old. Also, the water can't be more than 4 inches deep. Anything deeper and they exhaust themselves rising from feeding at the bottom to get air from the top. Yes, the baby fry can literally DROWN! Then, when they are so tiny, they require zooplankton to feed on and then they eat baby brine shrimp after that. That gives you an idea of how tiny they are and how easily everything else (female bettas and occasionally even MALE betta included) would consider them a fine snack.
The most filtration you can give betta fry until they are roughly 1 inch long is very gentle... submersible sponge filtration is suggested. They swim very slowly and easily get slurped into anything stronger than that. So as you can see, the best way to breed bettas is to separate a single pair into a 10 gallon with 4 inches of water (I suggest adding a teaspoon of blackwater extract to condition it) and go from there. It'd be a disaster to breed them in a large communal tank and some or all of your bettas would end up damaged or killed trying to mate in there.
