About pH

pH is an abbreviation for pondus hydrogenii, which also stands for “Power of Hydrogen” or “Weight of Hydrogen.” pH is a measure of the effective acidity or alkalinity of a solution. It is expressed as the negative logarithm of the hydrogen-ion concentration. Pure water has a hydrogen ion concentration equal to 10-7 moles per liter at standard conditions. The negative logarithm of this quantity is 7. Pure water has a pH value of 7. The pH scale usually is considered as extending from 0 to 14. As the scale drops towards 0, the solution becomes more acidic. As the scale rises toward 14, the solution becomes more basic.

Simply put, water with a pH less than 7.0 is acidic, a pH higher than 7.0 is basic, and a pH of 7.0 is always neutral.

While fish can survive in a wide range of pH values, most community freshwater fish and plants flourish between pH values of 6.8-7.4. Aquarium water quality is critical to the health of tank inhabitants, and for this reason, pH value should be tested weekly. While some fish, such as discus, prefer acid water, others, such as livebearers and African cichlids, prefer alkaline water.

Fritz Aquatics offers a variety of products to help control pH:

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