Join Date: Oct 2010
Location: Victoria, Australia
Your B. rutilans should be excellent parents. While there's always the exception to rules, based on my years of experience working with the coccina complex species, in almost all cases, both the male and female possess excellent paternal instincts.
Therefore, there is no need to remove either adult or the fry from the tank. In fact, I prefer to let my fry grow out alongside the parents.
These fish aren't difficult to breed provided your pair is compatible and water conditions etc. are to their liking. My wild bettas were constantly spawning. Sometimes before the previous batch of fry had even left the nest!
You will need live foods if you want the majority of your fry to reach maturity. While the fry will graze on infusoria and other microorganisms in the tank, BBS and other live foods should form the staple of their diet. At least until they are large enough to transition over to frozen or flake/pellets depending on your preference.
BBS is my recommendation. I rarely bother with microworms unless the fry are too small to take BBS. It can be a fiddly process, particularly if you're only feeding a small number of fry, but it does result in the highest survival rates and best growth rates. The only concern is in overfeeding BBS, which can lead to permanent swim bladder problems. So if you notice your fry are having difficulty maintaining buoyancy following a meal, I'd cut down on the amount being fed.
I've kept and bred wild bettas for years now. So if you have any questions relating to wilds, particularly concerning coccina complex species, I'm happy to help.