Hello. I have never owned a fish in my life and I don’t know anything about them. I am babysitting 2 Bettas for my mother in law who is out of town for 3 weeks. One of them already died on me and I feel horrible. Now the second one is acting like the first one did before it died. Here’s the rundown. She brought them to my house in small fish bowls- no heater, no filter. They eat pellets and she told me 4 pellets 2x a day. They have been with me for 2 weeks and I have already changed the water 3 times and used water conditioner she gave me. The first one died after a week at my house. The second one was looking good and happy but 2 days ago he stopped eating, and is acting lethargic- barely swimming- just hangs out at the top of the water. I have been doing research and I think it’s the water temp. But I have no way of heating this tiny fish bowl. I put Luke warm water in but it gets cold quick. I’m tempted to take him home to his big tank w a heater and filter that she usually keeps them in, but I don’t know if another change in water is going to shock his system and kill him. I don’t even know if her tank at home is still on or if she unplugged it all while she’s gone. Any advice??