1.8 times the water we have on Earth now is suspended somewhere it won't pick up too much energy falling to the ground. That conjures up an interesting picture of pre-flood people walking around on the underside of a glass-bottomed pool--only there's no glass, just the diminishing patience of the Lord holding up all the water.
If it's too low, it's cutting off part of the atmosphere. Or does it have perforations for breathing?