HOW TO IMPROVE WATER MANAGEMENT IN HATCHERIES
Maintaining high water quality is critical to the successful operation of a fish hatchery. To avoid pathogens, pollutants, and other contaminants, water is generally sourced from deep wells. Unfortunately, the high pressure in deep wells frequently leads to high levels or even super-saturation of undesirable dissolved gases. The presence of these gases can have detrimental effects on the delicate hatchlings.
Supersaturated nitrogen can lead to Gas Bubble Disease (causing lesions, convulsions, blindness and death). High levels of carbon dioxide lead to reduced growth and high mortality. The toxicity of high levels of hydrogen sulfide also leads to high mortality. Other dissolved gases, such as VOCs, have a detrimental effect on fish health. Conversely high levels of dissolved oxygen are required for proper growth and health. Poor dissolved gas management negatively impacts costs by increasing hatchling mortality and reducing quality.
Water Treatment Challenges Faced by Hatcheries
Dissolved Gas Management in Fish Hatcheries: A Case Study
The VAL™ continuously removes undesirable dissolved gases from hatchery water through fine bubble gas exchange and vacuum extraction. If left in the water stream these gases dramatically decrease the survivability of the fish hatchlings and fingerlings. By injecting oxygen into the processed water stream, the dissolved oxygen level is raised to the level needed to ensure healthy and energetic fish fry.
A VAL 600™ recently installed at a western US fish hatchery achieved the following dissolved gas results:
After installing the VAL™, the hatchery reported that the survival rate of their triploid walleye hatchlings increased by a factor of 5.3 and the survival rate of their diploid walleye hatchlings increased by a factor of 2.6. The hatchery coordinator noted that “This will make a huge difference in our sterile walleye program."
VAL™600 Single Pass Gas Management Performance
This VAL™ installation in Utah was evaluated and received the “Solar Impulse Efficient Solution” Label, an award for clean and profitable solutions. This is a groundbreaking and distinguished international label for positive impact businesses that are bringing together protection of the environment and financial viability.
The “Solar Impulse Efficient Solution” Label is attributed following an assessment performed by independent field experts. In collaboration with renowned institutions, solutions applying for the label must go through a neutral methodology based on verified standards.
Christophe Rivaud - Fish Hatchery General Manager Since 1994
Current Operation Produces Over 20 Million Fingerlings/Year