I recently bought a female crowntail betta. This is the first time I’ve had a betta, fish or aquariu. I had her in a 5.5 gal tank with a filter but not a heater as I live in a climate where I don’t need one. I brought her and a brand new tank home and got the tank set up and let her sit in her cup over night as I was told too. I was going to do a fish in cycling as I hadn’t learned about cycling prior to getting her. (Though I did a lot of research it didn’t come up) In the morning I followed steps to acclimate her into her new home. She wouldn’t eat (that I saw) but I figured she was a little stressed from the excitement of a new home. She would also hide in and behind the fake plants in her tank, but again I figured thats just what bettas do, other than that I didn’t see many other signs of stress, and she would still swim around and explore her tank; though I did have a filter in there that created a current that was too strong so I made a baffle that seemed to work well enough. I had her for three days before coming home and finding her dead. I tested the water and everything was at levels that should have been fine for her. I want to know what went wrong before I get another betta, if it was stress or something I did wrong.