Private water supplies in a large area of south west Wales are acidic in reaction and soft in character.
The pH of water is a measure of the hydrogen ion activity (acid base equilibrium). pH 7 is neutral. A figure above pH 7 is said to be alkaline.
Most spring water in the south west Wales area is in the pH range from 5.8 to 6.5, which is quite acidic.
There is a wide range of tolerance on the standards applied by the European Drinking Water Directive - pH 5.5 to 9.0, and in most cases the water will pass the required test.
Following the pH figure on the Public Analysts Report for water is a Langelier Index Figure. The more negative (-) this figure, the more corrosive the wear will be on plumbing. For example, a value lower than pH 1.5 will cause significant damage to copper pipework and soldered joints.
As a general guide, all waters less than pH 6.2 could be doing some sort of damage to metal fittings and pipework and copper cylinders and hot water immersion type heaters.
pH units are easy to install and need to be topped up periodically with limestone media. There is no need for an electricity supply.
The units are quite large however and need to be sited where they can be accessed for re-filling. The typical domestic unit size is approximately 10 inches in diameter and 50 inches tall.