The next hardest part of breeding bettas after getting the male to build a bubble nest, getting the male and female aquainted and not killing each other, is actually raising the miniscule fry.
For the fry I would already have some microworms and vinegar eels on hand along with brine shrimp eggs ready to be hatched, as well as any powdered of prepared foods that are designed for betta fry.
Personally I would try and only have the male make his nest in the longest most established tank that you have, and when he stops caring for the fry remove him, so that the fry have a tank which hopefully is already housing as much mirco foods as possible, live plants especially mosses will help with this. Rather than a shrimp in the tank a better idea maybe a snail if you are wanting to try and control/ reduce wood waste. But I would only add one snail because potentially you could end up with hundreds in a very short space of time.
I am glad the couple of attempts I had at breeding fighters failed, simply because after doing all the research I realised that I would have been very hard pressed to adequately house all of the potential fry.
Also keep in mind that the fry will have slight variation in their sexual development so every day you will need to be looking for males that need removing from the young females. Also with crossing various strains of betta with all their fin types it gets a lot harder to accurately sex them unless there is real aggression happening. Quite a few times I have purchased what was supposed to be a young female fighter only for her to "mature" further and turn out to be a male.
Best of luck with your project, I hope it all works out for you.
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