Betta Fish: Recovered from Fin Rot!!

This is our boy, Bluey Blue Blue. (My daughter named him :). He's a fighter. A few months after we got him, I noticed his fins getting ragged. Dreaded fin rot. He was really lethargic. I'm new to owning a betta, and I tried my best to understand what was happening to him, because I cleaned his tank regularly. I really thought he wasn't going to last much longer. But I noticed that the plant that I had placed in there with him wasn't doing so well. My guess was that the plant was dying and affecting the environment of the tank. So I removed it. Cleaned the tank a bit more regularly. I didn't use any kind of medication as advised, but I figured I just keep his environment clear of any other potential negative stimulus. After about a month or so I noticed that the ragged parts of his fins were healing. In the past couple of weeks, the healed areas were re-gaining his color. Now that it's getting cooler, I introduced a heater and monitor closely to maintain a good temperature for him. Now he's back to being very active and alert. He greets me every time I approach. Looks me straight in the eyes. I never thought I'd get this attached to a betta. I'm more of a dog person. But I really find myself taken by him. I'm so happy to see him thriving.