Is it blue or green?[1] Are you just seeing the blue liner many pools have? Or reflected blue sky? Or maybe something added to the pool water? Working from limi

Is it blue or green?[1] Are you just seeing the blue liner many pools have? Or reflected blue sky? Or maybe something added to the pool water? Working from limited data can be hard. If you've only ever seen one or few pools... [1] https://www.google.com/search?q=swimming+pool&tbm=isch https://www.google.com/search?q=swimming+pool&tbm=isch