If asked for their needs, I‘d say:
Keeping only - without the aim of reproduction - following parameters are ideal and should be met:
Temp: round about 77 F
pH: 4,5–6,5 (the higher the less likely to spawn)
GH: 1-6 (up to ~ 100 ppm)
Regarding these conditions, tiny live food like Grindal Worms, BBS and frozen food like Cyclops are the best choice as processed food won‘t usually be taken and will pollute the water.
It‘s best to keep them by themselves as they are easily outcompeted for food by other species.
They can be kept together with other fish of similar needs like small Boraras or Licorice Gouramis.
So if you intend to keep them and your other fish aswell and even get the Wilds to spawn, I‘d go for a small separate tank of ~ 6-8 gal with a simple sponge filter and use R/O water filtered over peet or water of equal softness filtered over peet.
It‘s really rewarding - even if one has to adopt to sitting quietly in front of the tank and waiting for their appearance and interaction (I definitely had to adopt😀)!
No substrate needed - just boiled oak or Indian almond leaves and ideally some worn out peet pellets. Java fern and Java moss will work as well as Anubias and Water Sprite as far as plants are concerned.
I‘ll attach pictures of my blackwater tank for Betta of the coccina family - not to be super savvy but just to give you an idea. I‘m new to keeping Wild Betta myself and have great support by some experienced friends - so I‘m passing on what they advised me and what worked out for me. I have fry every few weeks at the moment.
I‘m glad to help and answer any questions!