Ammonia, nitrite and nitrate tests are used to determine if the environment for fish is safe to live in or if the water is too toxic. Ammonia and nitrites are very toxic while nitrates are mostly harmless. To eliminate these chemicals, adding bacterial supplements will cause the cycle to continue at a faster rate. These tests also show the evolution of the nitrogen cycle in the tank. As the cycle progresses, ammonia will decrease while nitrites increase. Then nitrites decrease and nitrates increase. Then the nitrates decrease and your aquarium should be balanced. Some organisms are better adapted to live at certain temperatures, so water temperature must be monitored. Additionally, rapid changes in water temperature can cause problems for organisms in the aquarium. The water must therefore be maintained at a constant temperature to keep the fish in a stable environment with plenty of oxygen. Lower temperatures are able to retain more oxygen. Our fish can live comfortably between 68 and 82 degrees Fahrenheit. Cloudy water, water containing a lot of particles of sediment or organic matter, can make it difficult for organisms to acquire or create energy because it can obscure light and, depending on temperature. cause of turbidity, can lead to problems with other water properties such as ammonia, nitrite and nitrate. To avoid cloudy water, the best solution is to clean your aquarium and change the water often. Fish need dissolved oxygen to breathe, which allows plants to continue filtering water and producing energy. Although these properties are important to both the natural environment and a controlled ecosystem, they are supported in very different ways. In the natural environment, if there is little human intervention, the aquatic ecosystem...... middle of paper ...... about the requirements, adaptations and why you chose it. The black molly is a variation of the sailfin molly, or Poecilia latipinna. This fish is small and mostly black with short fins. It has also adapted its ability to live in different salt levels if exposed over time and therefore can eventually become part of a saltwater or freshwater tank. This fish shows dimorphism through a pointed anal fin and a large dorsal fin in the male and the round pregnancy spot in the female. Black bear cubs live young and can give birth to 10 to 60 cubs every 60 to 70 days. When breeding, the fish needs much more space in an aquarium. The fish is omnivorous and should be fed a variety of different foods such as algae flakes, tubifex, brine shrimp and freeze-dried bloodworms. We chose this fish because Jorge wanted to have black fish with our white sand at the bottom of our aquarium.