The Environmental Protection Agency has prepared guidelines for effluent discharges from commercial, federal, state, tribal, and private hatchery facilities. Phosphorous is generally the first limiting nutrient in fresh water for aquatic plant growth. Fish hatchery water effluent is a source of phosphorous and solids derived from uneaten, undigested feed and metabolic losses. With the use of more plant proteins (alternative ingredients) phosphorous availability in the feed and phosphorous as well as solids in the effluent has become more of an issue. Abernathy staff has worked on this specific problem but producing low phosphorous feeds and using them in feeding trials to test the efficacy of the feed. Results have been shared with the regional hatchery personnel and nationally.
