How much oxygen will aeration devices deliver? TT35
Published on May 12, 2014
 

How much oxygen will aeration devices deliver? - Tech Talk 35

None at all if the oxygen level in your water is at saturation!

Many commercially made aerators have been tested for their standard oxygen transfer rate, but that much oxygen can almost never be expected. Because the rate of oxygen transfer is concentration and temperature-dependent, an aerator will only provide its measured (advertised maximum) oxygen transfer rate when the oxygen level in the water is close to zero. Use this chart to estimate the oxygen transfer an aerator will give when there is already oxygen in the water. Example: if the water temperature is 68°F and the oxygen level is 4 mg/l, an aerator that is rated at 3 pounds of oxygen per hour will really only provide under 1.3 pounds per hour (3 lbs x 41 percent = 1.23 lbs).

*These percentages are approximate for fresh water at sea level.

 D.O. Level in Water Being Aerated 50°F (10°C)  59°F (15°C)   68°F (20°C)  77°F (25°C) 86°F (30°C) 
0 89%  90% 91% 92% 96%
1 82%  82% 82% 82% 82%
2 75%  73% 72% 72% 67%
3 67%  64% 62% 58% 56%
4 58%  55% 51% 47% 44%
5 52%  46% 41% 35% 31%
6 41%  36% 30% 24% 17%
7 34% 27% 19% 10% 3%
8 25%  17% 8% 2% 0
9 17%  8% 0 0 0
10 9%  0 0 0

0