Isu Students Dive Into New Tank To Study Fish Projects Seek To Advance Health Of Water, Rainbow Trout

A new 154-gallon rainbow trout tank at Idaho State University will provide chemistry classes with an aquatic environment they can use in learning how to analyze water and stream health.

And within two years, chemistry professor John Kalivas aims to use trout raised in the tank to develop a faster, cleaner, nonlethal method of analyzing trout health.

Chemistry graduate student Tracy Houghton is maintaining the tank in the university’s Physical Science Annex. Houghton also is writing the lab manual for the chemistry department’s sophomore quantitative analysis course.

Beginning in June, students will use Houghton’s manual to guide them through exercises analyzing water from the tank, measuring such factors as nitrogen cycle, dissolved oxygen and alkalinity.

Meanwhile, Kalivas is teaming with Idaho State biology professor and trout expert Ken Rodnick to develop a new technique for calculating fat and protein content in trout - indicators of fish health within stream segments.

The measurements also help fish farmers adjust feed formulas and schedules to produce the most commercially desirable meat, Kalivas said.

The traditional method requires killing the fish, drying the meat, then testing the tissue. It takes about three hours and requires using caustic chemicals that are expensive to buy and handle.

Instead, Kalivas and Rodnick are researching a way to make the measurements in minutes on live, anesthetized trout using near infrared spectroscopy. A spectroscope will be used to measure how light acts when shined through the trout’s tissue. The amount of light reflected will yield fat and moisture information, and moisture information correlates to protein.

A $5,000 Dreyfuss Foundation grant helped start the tank, and the Hagerman-based aquaculture company Rangen Inc. has agreed to continue supplying the tank-related projects with trout.