Could just be a bacteria bloom, regarding the cloudy water. It happens on newer tanks.
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pH is about CO2, not oxygen. Adding an airstone won't alter the pH, since the air comes from the room. The CO2 in the water will always be relative to the air, and an air stone will just speed up the process of it balancing itself.
You need more fresh air in the room (open windows or an exhaust fan), or take skimmer air from a line that goes outside.
If none of those are good options, a CO2 filter on the skimmer is something to research if you continually have pH lower than 7.8.
The last option is no more breathing in the house, but that may have undesirable side effects...
Could just be a bacteria bloom, regarding the cloudy water. It happens on newer tanks.