WATER CHEMISTRY

ALLBRANDS does free water testing in our retail shop, we have a computerised photometer for the most accurate readings that automatically calculates how to balance your water depending on a number of factors including the season (summer or winter), your pool size, pool age and the type of pool, for example fibreglass, concrete, etc.

The table below should provide you with an approximate idea of what you should be aiming for with your water quality however speak to ALLBRANDS for more exact information relating specifically to your pool.

PH
pH is a measure of how acidic or basic water is on a logarithmic scale between 0 and 14. From 0 to 7 is acidic, 7 itself is neutral and any reading above 7 up to 14 is basic. Every liquid that enters your pool has a pH value, the human eye at has a pH value of 7.35 which is very slightly basic and within range of the correct pH levels for your pool. To have pH in balance we adjust the water with additions of pH increasers (bases) or pH de-creasers (acids) to achieve the range of 7.2 - 7.8.

If your pool water test shows a pH value below 7.0 the water will be corrosive (acidic) and you will need to add a base to bring the pH into a more basic range. It doesn't take long for a low pH condition to weaken vinyl, strip heat exchangers and pit plaster. Conversely if the pH is above 7.8 it will be in a scaling (basic) condition and you will need to add acid to bring down the pH to prevent the formation of scale or calcium deposits.

Total Alkalinity
A close cousin of pH, the level of alkalinity in the water is a measurement of all carbonates, bicarbonates, hydroxides, and other alkaline substances found in the pool water. pH is alkaline dependent; that is, alkalinity is defined as the ability of the water to resist changes in pH. Also known as the buffering capacity of the water, alkalinity keeps the pH from "bouncing" all over the place. Low alkalinity is raised by the addition of a base (similar to pH); sodium bicarbonate is commonly used. High levels of alkalinity are lowered by the addition of an acid (similar to pH).

A very important component of water balance, alkalinity should be maintained in the 80-120ppm range for concrete pools and 125-170ppm for painted, vinyl, and fiberglass pools. Levels should be tested weekly.

Calcium Hardness
Scale is the whitish deposit inside your kettle and on the cells of your chlorinator which consists of calcium carbonate which has come out of solution and deposited itself on surfaces. It is a combination of carbonate ions, a part of total alkalinity and calcium, and a part of the Calcium Hardness level. The test for Calcium Hardness is a measure of how "hard" or "soft" the water is. "Hard" water can have high levels of calcium and magnesium. If these levels are too high, the water becomes saturated and will throw off excess particles out of solution which then seeks to deposit themselves on almost any surface inside the pool. They can be attracted to ladders, lights and in extreme cases deposit themselves as very small crystalline clumps - all over the pool surfaces. Calcium Carbonate scale; a "white-ish," crystallized rough nodule.

If the Calcium Hardness levels are too low, the water is under-saturated. If under-saturated, the water will become aggressive as it attempts to obtain the calcium it needs. Such "soft-water" will actually corrode surfaces inside the pool which contain calcium (like pool plaster) and other minerals to maintain its hardness demand.