Just as a test, put a water sustainable plant in a glass bowl by the window. you'll notice that the plant will do fine, roots will start growing but there will be algae all along the roots and glass.
Any tank recieving natural sunlight will have problems with algae. This is the equivalent of having a high light tank. Given your altitude, you will be receiving far more light than the rest of us. I just came back hiking in China hitting a peak of 3800m (8400ft) above sea level. I recieved a pretty nice burn in under 10 minutes while my clothes dried (we took a refreshing walk under the glacier waterfall at the peak of our hike).
You may hit a balance with heavily planting, dosing with Excel and CO2 but its a lot of work for something that really should be much simpler and enjoyable.
Any tank recieving natural sunlight will have problems with algae. This is the equivalent of having a high light tank. Given your altitude, you will be receiving far more light than the rest of us. I just came back hiking in China hitting a peak of 3800m (8400ft) above sea level. I recieved a pretty nice burn in under 10 minutes while my clothes dried (we took a refreshing walk under the glacier waterfall at the peak of our hike).
You may hit a balance with heavily planting, dosing with Excel and CO2 but its a lot of work for something that really should be much simpler and enjoyable.