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About 71 percent of the Earth's surface is water-covered, and the oceans hold about 96.5 percent of all Earth's water. But water also exists in the air as water vapor, in rivers and lakes, in icecaps and glaciers, in the ground as soil moisture and in aquifers, and even in you and your dog.
Answer:
If the pH of the water was too high or low, if the temperature was too hot or cold, or even the climate in which is provided to them inside of the tank can abiotically effect the population of the tank.
Explanation:
This is because of their natural abilities and capabilities. For reference: Many people like different temperatures whether they want to or not its a preference and if they were to change their location in which it has a new climate it would effect the way that they do things. Such as, a change in clothing.. But fish do not have clothes. Therefore it is unfortunate that some of their population does die naturally even in the wild do to this.
