I just noticed that the water in my turtles tank kinda has a film over it in some places. If the light hits it right you can see a rainbow. I'm going to try and change some of the water today because it's starting to smell turtley. Is this film bad? Is it some kind of alge like thing? I have a fluval 404 and I'm going to rinse some of the media today. Just wondering if anyone else had this problem and knows what it is. I don't put anything in my tank (special chemicals) that would cause this. Thanks for reading. 


