TPS: Small Fry to Go - Week#7; A Student's Perspective; "Toxic Negativity – Nitrites vs. Nitrates"

There must be something in the water, because TPS students are as excited as ever about the ‘Small Fry to Go’ project. However thanks to the students' diligent use of the 5 in 1 aquarium testing strips, it is certain what is in the water is not nitrites or nitrates.

No, the previous sentence does not contain a typo, nor am I confused. As with much of the nomenclature in chemistry, compound names are vast and diverse, but many still sound and look similar. And along with many other objects in chemistry, though nitrites and nitrates share their two identifying elements, their unique structures, ratios of atoms, and effects on organisms are very, very different.

Nitrites (NO2 – ) are anions (negative ions) which can be found naturally in freshwater or saltwater. Under normal conditions, the concentration of nitrites in both waters is extremely low, and has no adverse effect on many fish, such as trout. But, in much larger concentrations, nitrites can become quite toxic to fish, as they begin to alter the hemoglobin (oxygen-carrying compound) in red blood cells. Nitrites usually build up at the bottom of lakes or in particularly acidic waters.

Nitrates on the other hand (NO3 –), are found in man-made fertilizers, and large deposits in the earth. Nitrates can get into water systems through runoff from land or through bacteria that convert other compounds into nitrates. They collect naturally in freshwater systems closer to land and can cause many problems for fish. Interestingly enough, nitrates can alter the chemistry of ecosystems, causing them to favor certain organisms over others.

Both nitrites and nitrates have a similar toxicity, but nitrates are more prevalent in freshwater ecosystems. Regardless of their differences, it is reassuring that the TPS students are keeping watch over our treasured ‘Small Frys’ as we head into our last week of raising and caring for them before we release them into their natural habitat.

Alexander Choi - Sophomore, Temecula Preparatory School