Hardness is usually expressed as temporary or carbonate hardness and permanent or non-carbonate hardness. The term temporary hardness is commonly used because carbonate hardness can be removed by precipitating the calcium and magnesium cations or salts by boiling. The most common method to reduce hardness is to dilute the hard water with distilled water. Other means include use of a commercial water softener such as reverse osmosis units or ion exchange gel filters if large quantities of soft water are needed. The pH is a measurement of a water s acidicity and indicates a change from a neutral pH of 7.0.
Neutral water contains an equal balance of hydrogen ions and hydroxide ions.
If small quantities of water are needed, reduction of pH is generally a simple matter and can be achieved through peat filtration. When using a strong acid to reduce the pH, be sure to run several tests to determine how much acid is required to reduce the pH of a given amount of water to the desired level. When handling strong acids, review and observe all safety precautions to prevent accidental spills or exposure to eyes and skin. Many species of fish produce eggs only once a year while some others produce eggs repeatedly over the course of a spawning season. Lemon tetras fall into the latter category.