are my fish sick?

Question
Hi,

I have had a 20 gallon tropical freshwater fish tank up and running for about 2 months now. I have two balla sharks in the tank about two and a half inches each in size. I'm running a penguin bio wheel 150 in the tank and keep the temperature at about 77 F 24 C. I feed them twice a day with tetra color tropical flakes. There was no algae growth for about the first month and a half in the tank. But within the past two and  half weeks there has been a large amount of algae growth in my tank. Also within the last week the tanks water has become very murky and my fish have a white film coating on there bodys. There eyes do not look milky and its not ich as it dose not look pimpley or sandy. Its more like a milky coating. Do you have any idea what this problem could be? Any help as soon as possible would be greatly appreceated.

Answer
Hi There,

Algae requires light and nutrients to grow. If the tank receives too much light, is over-fed, or is over-stocked, algae problems will usually occur.
I recommend reducing the amount of lighting and feeding.

This grey film is usually excess mucus that the fish has produced in response to an irritant, such as poor water quality or even chlorine from the tap water as well as a host of microscopic parasites such as Costia, Chilodonella, Trichodina or skin and gill flukes. Test the water to eliminate this as the cause of the problem.

Hope this helps,
Chloe :)