I am hearing a lot about how long bettas can go without food (up to two weeks supposedly?) if you have to leave for some reason, but what about the water cleanliness? I am having plans to visit family friends for Christmas and will be gone at least two weeks - I am thinking I will need someone to change the water for me. I'm guessing this is correct? It just never gets mentioned along with the feeding times, and I would think it is rather important for the fish's health. And this is with a filter, I forgot to add.