Colloids, like truly dissolved substances, never settle out. If several salts are added to water, they will dissolve and precipitate until equilibrium is reached according to the solubility of the possible ion combinations. Because of this, ground water and spring-fed streams will have more dissolved solids than streams and lakes fed from surface water. Therefore a lake at 12,000 feet will contain less O 2 than a lake of the same temperature at sea level. If bubbles passing through water differ from normal air, the water will tend toward equilibrium with the bubbles.
Hydrostatic pressure increases the amount of gas that can remain in solution.
At 100 meters deep gas will remain in solution up to 10 atmospheres pressure if there is a source. Sources may be decomposition producing CO 2 or a slow leak of natural gas or volcanic gases. Effect of Temperature Solubility of any inert gas varies inversely with temperature. As the water temperature goes up, so does the vapor pressure of water and the partial pressure of other gasses goes down. At boiling, the vapor pressure of the water equals atmospheric pressure and no other gasses can be held in solution.