Dawson, V. K., and Marking, L. L., 1986, An integrated system for treating
nitrogen supersaturated water: The Progressive Fish-Culturist, v. 48, no. 4, p.
281-284.

Abstract:

Groundwater is commonly supersaturated with nitrogen and must be treated it is
used for culturing fish-- especially sensitive species such as lake trout (Salvelinus
namaycush ) and Atlantic salmon (Salmo salar ). The  authors treated water with an
integrated system that passed water through a packed column aerator, then  through
a vacuum degasser, and finally through another packed column aerator (installed as
a backup system).  In well water passed through packed columns, nitrogen gas was
reduced from 131 to 105% of saturation and  oxygen was increased from 23 to
86% of saturation. With a vacuum pressure of 3 in Hg, the degasser further 
reduced the nitrogen gas from 105 to 99% of saturation, and oxygen saturation
remained near 86%.

Keywords:

aquaculture-systems, ground-water, degassing, water-treatment, oxygenation,
fish-culture