I just want to say that i absolutely agree on every suggestion that teeneythebetta wrote. Just want to add something. I am not sure though about well water. Can you buy stress coat? You can use it as a water conditioner and it also good to use it in general for fish. Or i will recommend Prime by Seachem.
Also make sure you rinse very well new 1.5 bowl with hot warm water before you use it. Don't add salt. You don't need to use it on regular basis. But i would suggest to have it as emergency kit if you ever need to treat betta (i hope not).
I use aged water all the time because it convenient. My bettas during the summer time without heaters so i just put water conditioner and let water sit overnight. This way new water temperature the same as his and i don't have to worry about it. In the winter time i do the same but i just add warmer water that i preapare 30 min before i change them. Also i know that when you age it some chemicals will evaporate.
Also you need thermometer so you can see temperature when when you change him. Especially when you do 100% water changes. I like this kind because you can just stick it on outside of the tank and when you pour new water in the tank you see it right away. I like ATI Horizontal Aquarium one $2.16 very convenient. I have it. When i change the water it show it right away and i see the difference so i know if i have to add warmer water .
Also not sure if anyone mentioned if you ever will buy live plants it can carry disease so be careful. Always quarantine it in the water with NO water conditioner for a few weeks. And actually you have to do it with new fish if you ever want to put another fish in the same tank. Of course not in 1.5 or 3 gall though.
You probably know that you can have 2 bettas in the tank, male or female.
posted at the same time i didn't see you post :)