With no filter they will need frequent water changes. Don't use any treatment other than plain dechlorinator, it could do more harm than good. With the small "tanks" frequent water charges will be easily doable, you don't need to cycle, just never miss a water change. Let's be realistic, other than possibly the 5 gallon, the cycle would be permanently unstable anyway.
The heaters are another matter and cannot be avoided as they must be kept warm.
Feed sparingly, I'd do 4 times a week. And add live plants, particularly floating.
Check out the care guide for how much/ how frequently you need to water change uncycled containers.
Marble Rosetail OHM Species: Betta (pronounced bet-uh), also known as the Siamese or Thai fighting fish. Scientific Name: Betta splendens (although the domesticated versions are a result of breeding wild betta splenden complex members together) Wild Betta Splendens Lifespan: 2 - 10 years...
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