Alright, well, I've had my 10 gallon tank set up with tap water, gravel, a cave, and water dechlorinator for about a week now. I got a heater and a thermometer at the petstore the other day and while setting these up it came to my attention that there is a strange very thin layer of slime on the top of the water. When looking from underneath to the top of the tank, this slime looks kind of oily. When sticking my fingers in the water, the water is tangibly slimey. I dropped a few pellets of food into the water a few days ago when I decided to cycle my tank using that method (only to decide to use ammonia later). I noticed right after that that the water had gotten very cloudy.
Question: Is this normal? If not, what could have caused the slime? The 10 gallon was used about a year and half ago as a frog tank. I used vinegar to get some of the stuck-on stuff off. Could this be the cause? Could I not have washed the tank out well enough?
Should I dump the water, scrub the tank again, and put fresh water in?