This my turtle tank (so don't worry, there is no fish in there!) It's been like this for the past week and a half. Sunday, I did a 50% water change. And, since monday, there has been no lights (for red-eared slider aficionado, don't worry, my Michaelangelo has had his basking time in another spot!) For the little history, my previous tank failed me about 3 months ago, so I had to set up this one pretty quickly, so I did put my RES in it right away (not quite sure if it is important for the tank to be cycled since it is a turtle only one but I know it is not. I had 2 ppm of ammonia, 5 of nitrites and 20 of nitrates Sunday). I have a fluval 306 filter and the tank is a 45 gallons bowfront. I know this is not a usual freswater aquarium but I would really appreciated any help!