Petroleum, a fossil fuel, supplies more energy to the world today than any other source. The United States is the world's leading consumer of petroleum; in 1994, Americans used 7,587,000 barrels of oil per day.
Frequently test for ammonia and nitrite (you want both to measure zero). A pH test is also handy to ensure your goldfish's water is not too alkaline or acidic. This can be purchased at any pet store. Do not modify the fish's water, however, unless it is significantly different from neutral.
goldfish with white like coating on them. My goldfish in my outdoor pond (4900 litres) have started to get a white film on their bodies and the smallers ones are on top of pond not doing well at all. i have tested water and it's PH is high. I have a large filter system and the water is very clear. There is a mixture of koi and goldfish in the pond.