Is pH Really That Important? The pH is one of the most important factors in pool water balance, and it should be tested and adjusted on a weekly basis. pH is the measure of how acid/ alkaline the swimming pool water is. A pH of 7.0 is neutral - below 7.0 is acidic, above 7.0 is alkaline. It should be kept within the range of 7.2-7.8. What happens when the pool is too acidic? (pH is low): 1. If your swimming pool is Marbelite or plaster, the pool water will begin to dissolve the surface, creating a roughness which is ideal for pool algae growth. A similar result occurs in the grouting of tiled swimming pools. 2. Metals corrode - and this includes swimming pool equipment, pipe fittings, pump connections, etc. As the swimming pool walls, and metal parts corrode, sulphates are formed. These sulphates are released from the water onto the walls, and floor of the swimming pool causing ugly brown and black stains. 3. Chlorine, which is used as a disinfectant in the swimming pool water, is activated and lost to the atmosphere very quickly. The water is not being sanitised, and we are throwing away our money by adding chlorine when the pH is too low. 4. When we swim, our eyes and nose burn. Our swimwear fades, and perishes. Our skin gets dry and itchy. What happens when the pool is too alkaline? (pH is high): 1. The calcium in the swimming pool water combines with carbonates and forms scale, just like in our kettles. This calcification is seen most at the waterline, where it traps dust and dirt, turning black with time. 2. The swimming pool water starts to become cloudy or murky and it loses its sparkle. Catch yourself buying clarifier frequently? This could be the result of your pH being too high. 3. The calcium carbonate has a tendency to plate out on the sand in the swimming pool filter, effectively turning it into cement. So your filter becomes a cement filter, and loses its ability to trap dirt and other debris from the pool water. 4. As the pH rises, the power of the chlorine to act on foreign particles is lost. At a pH of 8.0 the pool can only use 20% of the chlorine you put in. So 80% of it goes to waste and you would need 5 times as much chlorine to provide the disinfection you need. Swimming pool maintenance The five keys to maintaining water quality in your swimming pool include: Filtration Chlorination pH level Total alkalinity (TA) Calcium hardness. Filtration The water in your pool is pumped through a filter to remove debris and particles. How long you need to run the filter depends on the size of your swimming pool, and the horsepower of your pool pump. If you are unsure, check your instruction manual or consult with a pool maintenance company. Remember, that even when you are filtering your pool according to specifications, about 35 per cent of the water still won't be filtered. Chlorination Chlorine is a chemical that disinfects the water and helps to remove debris. You should use a chlorine stabiliser to extend the chlorine's half-life. Generally, the longer your filtration cycle, the less chlorine you will need. Similarly, the more chlorine you use, the shorter your required filtration cycle. Remember that your chlorine requirements will be affected by a range of factors, including your pump and filter system, water temperature, water level, amount of debris, and the number of swimmers in your pool. pH level The pH level indicates how acidic or alkaline the water is at any given time. A pH level of 7 means that water is neutral; above 7 means the water is alkaline, while below 7 indicates acidity. You should aim for a pH level of between 7 and 7.6. If the water pH is higher than 8, anyone who swims in the pool is at risk of skin rashes, while a pH of lower than 7 can sting the swimmers' eyes. Some of the many factors that can affect your pool's pH level include heavy rain, lots of swimmers, and pool chemicals. Remember to regularly check your pool's pH level. Total alkalinity (TA) Total alkalinity (TA) means the sum of all alkaline chemicals in your water. If TA is too low, the pH balance can become unstable; concrete and painted pool surfaces will also deteriorate over time. TA and pH are interconnected; for example, raising the TA could also raise the pH. Make sure you don't disrupt your pool's pH when adjusting the TA, and vice versa. Calcium hardness Calcium hardness refers to the amount of the mineral calcium dissolved in your water. Low calcium levels will deteriorate pool surfaces, while high calcium levels will leave a 'scum' or scale on surfaces and equipment. General water quality suggestions Be guided by pool professionals, but general suggestions on maintaining good water quality in your swimming pool include: Check your pH and chlorine levels daily. Preferably, these tests should be done before the first swim of the day, to make sure the water quality hasn't altered overnight. In very hot weather, it is a good idea to check the pH, and chlorine twice daily. Remember that heated pools need more chlorine than non-heated pools. Brush, and vacuum your pool on a regular basis. Regularly check the pump, skimmer boxes, and other pool equipment, and repair or replace parts as necessary. For more help visit www.poolhelpusa.com