So I just got a new tank for my betta about a week ago. I was noticing that the water was starting to get kind of cloudy a little too fast. When I first put water in, it was cloudy the next day. Not really cloudy, but to the point that it looks a little dirty. I did a 100% water change yesterday and rinsed out the gravel more to make sure it wasn't the gravel making the water cloudy, but lo and behold, today the water was cloudy again. My 2 gallon bowl wasn't even like this. What could be going on? Also, there's a strange, film-like substance at the top of the water... I've seen people write about this on here, but I don't remember what was said about it.
Here's my specs:
5.5 gallon tank
No live plants
Water is normally anywhere from 72-80 degrees. (my heater isn't the best and cools down at night)