Function

• Water that is naturally soft is devoid of dissolved solids. Most tap water sources do not produce this type of water, thus, some individuals decide to utilize a water softener to achieve this result. This process cannot alter tap water to the extent that it will contain no dissolved solids, rather, its function is to rid the water of calcium and magnesium through a neutralizing process, and replace it with softer minerals, specifically sodium and potassium.
  
  

Significance

• Many fish are sensitive to potassium and sodium, and as a rule, do not adjust well to changes in the pH of their water. In hard water, the pH balance is maintained by substances like bicarbonate, which is alkaline in nature. This counteracts the acid forming properties which naturally occur in fish and their aquatic environment, creating a balanced habitat.
  
  

Considerations

• Tap water is generally hard and contains more of the alkaline substances needed to maintain safe pH levels for fish, making it an ideal habitat. According to the Natural Wildlife Federation most fish do not require a soft water environment, but have obvious difficulty adjusting to it, and some will not survive the change.