It is pretty important that any temp changes be done slowly. If you are doing room temp I would just set out a gallon jug of the water overnight or at least a half day before your changes to make sure it is the same temp.
Other then that it sounds like a normal betta. They swim around and they do sleep, you can tell because the will be still but when you come over they look up like "oh, hello?". The flaring is a great sign I think-a sassy betta is usually a happy one
If it's an adjustable heater, turn the heater down all the way, and slowly increase it over a few days.That's good to hear about the sassyness! The previous betta I had, Webster, he was so friendly. Would pretend he was a whale too.
I do let the water sit out overnight so room temp is not an issue. I'm just worried for when I get him out of the tiny bowl and into a 10 g! The heater will be a bit of an issue at first.
Your fish you can do what you want but to me 1 gallon is too small. Fish swim and to do so requires room. A 10 gallon tank can be bought for 10 bucks, lack of funds is a poor excuse. We know bettas can live in a cup but to me that's just not right. Do whatever your continence is ok with.Betta has plenty of room to move around. Yes it is vulnerable to temperature swings--but I have no job and I am almost always home besides--my place just does not get cold. Minimum according to who? Not breeders or people who keep show bettas. It is true that some have betta barracks but many do not.
This is all your opinion. To counter I have a healthy and to all appearances, happy fish. That's my goal in fish keeping, not to please the worry warts.
