Aquarium water pH
The pH measure water`s acidity or alkalinity. 7 means neutrality; under this value this water is acid and, up from this, basic. An acid water doesn`t contain dangerous acids; in forest`s rivers it fills with 
organic materials and acids provided by the decomposed plants (humus); it can be recognized by it`s light yellow color. Generally, aquatic`s lift is possible only between 5 and 9. These extreme values may be obtained rarely in the aquarium, where the pH varies between 6 and 8, depending on water`s type. In aquarium`s science books is talked about an acid water when the pH varies between 6 and 6.8 and about a basic one between 7.2 and 8.
Between 6.8 and 7.2 it is consider a neutral water. These changing values of the pH are because of the biological alternations. The carbon dioxide produce by creatures when it`s night makes water to became more acid and the pH is decrease slowly. In time when it is absorbed by the plants the value is increasing again. A weak vary is considered normal but big difference show that there are problems. The pH is a good indicator of aquarium`s equilibrium, and it is a constantly measure indicator. With the help of a colored indicator we are able to compare the obtained colors on a calorimetric scale; there are electronic pH-meters too.
pH adjusting
Water doesn`t certainly have a likeable pH for the fishes. Furthermore, when an aquarium is functioning the pH can slowly but regularly increases or decrease. Some products can help pH adjusting but there are different ways which help us to do the same thing:
- if the pH is too high we can add a more acid water, limit water`s agitation, or filter the water with the help of the peat which will eliminate some acids.
- if the ph is too low we can add basic water, we care grow water`s agitation (which help the removing of carbon dioxide or we can filter the water with a calcareous material.