I was trying to make an interesting moon of a gas giant similar to Jupiter with a liquid ocean of water. The moon orbits in the equivalent orbital space of Io and is about twice the size of Mars. This moon is kept warm by greenhouse gases in the atmosphere and tidal heating. The moon's atmosphere has a trace amount of Sulfur Hexafluoride, which is a greenhouse gas much stronger than CO2.
This gas is produced by the large amount of volcanoes on the moon, which also produce other chemicals such as Fluoride Acids and Sulfuric Acid, which makes the planet's atmosphere and oceans very acidic. The ocean has an average pH of 3. It is also very salty, which keeps it liquid even though the average temperature of the moon is -15 degrees Celsius. My goal for this moon was an ocean planet with a toxic atmosphere located in orbit of Jupiter. Is this planet realistically possible in real life?