Saltwater aquarium

Students at Harvey Mudd College monitor a saltwater aquarium to study the chemistry of a marine ecosystem. When fish and food are introduced into the aquarium on day 0 in panel a, organic compounds are metabolized to produce NH3. Anunonia is toxic to marine animals when the level exceeds 1 ppm but, fortunately, it is removed by Nitrosomonas bacteria, which colonize the aquarium filter and oxidize NH3 to nitrite (NO2). Alas, NO2 is also toxic at levels above 1 ppm, but it is further oxidized to nitrate (NO J) by a second colonization of Nitrobacter bacteria. The natural process of oxidation of NH3 to NO2 and NOJ is called nitrification. 

NH3, NO2, and NO3 concentrations in a saltwater aquarium at Harvey Mudd College after fish and food were introduced into the tank on day 0. Concentrations are expressed in parts per million of nitrogen (i.e., pig of N per mL of solution). [Data from Hal Van Ryswyk, Harvery Mudd College.]... 

E. Box 6-1 discussed nitrogen species found in a saltwater aquarium. Now we consider the measurement of ammonia in the fishtank, using an ammonia-selective compound electrode. The procedure is to mix 100.0 mL of unknown or standard... 

The saltwater aquarium is filled with artificial seawater made by adding water to a mixture of salts. 

Suggest a reason why saltwater fish die when they are suddenly transferred to a freshwater aquarium. 

Without looking back, he runs through the hallway of his quarters. The vibrations from the slammed door caused his Miro lithograph to fall from the wall and the fish in his nearby aquarium to scurry for cover behind some aquatic plants. His saltwater pycnogonid jams itself behind a rock. It is shielding itself from the commotion outside the confines of its glass-enclosed universe. 

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