Oh, I don't have any ideas to help but I'd love to learn about these bettas & breeding them.
Congrats! I hope you know a community tank is not ideal & if you can move the eggs to a small tank, well, I would...Next time, in a month or so, try moving the pair to a smaller "spawning" tank before they breed. Try feeding them some extra protein rich or better, live foods to get them ready. The males, if like other bettas, will care for the eggs & youngest fry...but then it's all on you when they tire of parent stuff. There's a learning curve for many fish being new parents. It can take a few batches of eggs for them to get the right idea. Don't give up!
Sorry about the well-overdue response; completely forgot AC existed for a little while.
Thanks for the info and heads up! Rather expected, but still disappointing news; the male ended up swallowing the eggs at around Day 5 of incubation, but for what reason I don't know. He was displaying excellent brooding behavior and diligence... Maybe it was all just too much for him.
Think I might've neglected to mention that the species is a mouthbrooding one; it'd be a mite bit difficult attempting to extract a tightly-clumped bunch of eggs from a mouthbrooder this small. Doesn't mean I can't try, though I think it might possibly be too stressful or potentially harmful to the male.
Unfortunately, my tank options are fairly limited at the moment, as I do not have any tanks reasonably suitable for the pair that are large enough besides the 75G. Luckily, pallifina are probably the best community-oriented betta species I've ever kept; they're very enthusiastic eaters (to the point that they'll actively attempt to eat food far too large for them and steal from larger tankmates) and seem to be completely passive to all other fish. They are hardly fazed by some of the less-friendly denizens and the inhabitants of the tank have all practically come to ignore them at this point.
Whenever I moved the female into a drastically new environment (only did it twice with this female), it went through a dramatic reduction in appetite and did not show any spawning behavior for quite some time; I suspect the male'd dislike similar environment changes as well, though it certainly would be much easier if I could move the fishes into a dark, solitary tank.
I have been feeding the fish a protein-rich diet in general; bits of NorthFin Carnivore pellets, brine shrimp, bloodworms, chunks of krill , chopped-up silversides, etc. are all part of their staple diet (though I don't feed actively feed them krill and silversides; they just tend to steal it). The two have free reign over how much they eat, as usually they're the first to receive the food going into the tank (and there's always more than enough for them in general). They always end up taking more than their allotted share, and are so greedy they assume nearly everything's food- the female always tries to eat my hand during water changes! A couple days ago, I heard a quiet splashing noise from the tank (aside from the powerhead and filter) and entered the room to find that the pair was constantly leaping out of the water, one after another in almost perfect sync, to try and grab a couple of bloodworms that had dried up on the lid. It was quite the comedic spectacle; I wish I had managed to take a picture or video of it.
The female has taken up breeding stripes (again), but the male is quite unwilling to spawn. In a suitably large tank, a ~3.1 group would probably yield better spawn rates, I think. Males seem to take the most conditioning before spawning, while the female requires nothing but good food and clean water to spawn again after laying eggs within two or so weeks. Hopefully I'll get another batch of eggs soon, and maybe this time I'll either separate the eggs into a tumbler or leave the male alone and hope he incubates them for the full period this time.
