Betta Fish: My first betta :)

Hello everyone, this is my first betta fish, Shinji, and his tank! I got him about 2.5 weeks ago and he was in pretty rough shape (he was the last one left in a tiny cube at the shop). I think the fins on his belly have grown quite a bit since then, but I would love to get more opinions and advice!

The dark picture is from day 1 and the lighter one is from today.

I treated the water with Baktopur on days 1 and 3 after he came, then changed 1/3 of the water after a few days. I then worked on the bacteria by adding more in, doing coffee-cup water changes and adding bottled water every few days and topping up evaporation with distilled water.

He’s a sweet guy who loves exploring and hanging out near whoever is sitting next to the tank. He seems very friendly and I haven’t seen him flare at all. I wanted to get shrimp, but now I’m kind of scared they might go for his fins, and I don’t know how often that actually happens. 🙈 I also have small plant snails and one assasin snail to keep their numbers down.