Hi all! I currently own two betas in a divided 10 gallon tank, 5 gallons for each fish. A veil and a delta.
Hopefully more people are educated now, but the minimum gallons for a beta fish is 2 gallons, with a heater and filter. Bowls are an absolute no, most cannot accommodate a filter and heater, and don't provide the necessary surface area and much more things are wrong w/ bowls. Heaters are needed. Betas are tropical fish, and need warm temperatures to flourish, the recommended temps. being 75-85 F. Cycled tanks [the nitrogen cycle] are a somewhat confusing topic, but with the right research it's easy. People should NOT breed betas unless they've done PROPER RESEARCH. Research is necessary for ANY pet.
Breeding shouldn't be done unless you plan on getting several more tanks (cycling the tanks, adding heaters, filters, plants and cleaning weekly), because betas need to be separated. I think the only way you can keep them together is if you have a sorority of female betas, or keep two betas from a young age from the same batch they were born (even then, they can be aggressive). Your fish cannot really speak to you, so if you get two betas and put them together, you might think they're happy and all, but they will only tolerate one another before it becomes too much. Back to breeding, you should do tons of research and be sure you're ready for all the hard work it can bring. Males and females will fight, not all will breed. And if you sell the offspring, chances are they'll go to a bad home. (+ there are thousands of betas all over in small cups, waiting to be given better homes).
I think anything is better than being in a dirty, cold cup. BUT to give it the good and happy life it deserves, a beta needs an owner that has done research.
2 gallon+ tanks with filters and heaters are needed for a beta fish to thrive. In my opinion, they are the most stressed fish of all. Being stuck at a pet store in a small, unfiltered and cold cup puts tons of stress on their bodies. Vases, bowls, and any other habitat other than the ones mentioned before will easily kill a beta, and if not quickly, then it will surely make it's life miserable before it's death. Real plants are great for them, but I also use fake plants that are SILK. Any plants that are sharp, hard or not silk pretty much will easily do damage to a beta's sensitive fins.
I hope people do a lot more research on betas, it's not just buying a cheap and small beta bowl, the betta, filling the bowl with water and rocks and dumping in the beta. It's more difficult than you think. It's getting a 2+ gallon tank, setting up a filter and buying cartridges, cycling the tank, getting a heater, and cleaning it weekly. Along with using a balanced diet with your beta (bloodworms, pellets, etc.) and treating any ailments such as finrot, bloat, etc.