The pH of the water varies depending on factors such as the type of substrate, number of plants and fish in the aquarium, etc. There are rocks that can alkalize the water excessively. In any trade specializing in aquarianism we can get pH meters.
There are also chemicals to acidify or alkalize water. They are used to condition the water we get from the tap, before it is used in the aquarium.
It may seem somewhat tedious, but it is very important that our aquarium has the right pH for every species of fish and plants.
Water, apart from H2O molecules, has hydrogen free ions. That set of ions has a weight, that weight defines the pH value.
These hydrogen free ions can be hydroxyl radical negative (anions) or hydrogen positive (cations). Cations will determine acidity. Its weight in grams per liter of water will give us the acidity value. Neutral water is equal in weight of anions and cations.
The pH scale is logarithmic, ranging from 0 to 14. A pH point means a concentration ten times greater or less than the previous or subsequent concentration on the scale. We can then say that a pH 5 is 100 times more acidic than one of 7 (neutral).
It is clear that one point of difference, becomes a gigantic difference in concentration, which will undoubtedly affect the health of plants and fish.
© Adrián Blanco 2005 / 2010 — No full or partial reproduction of text and/or images without explicit written consent of the author.