...Let me introduce myself; I’m Nick from Agua Pura Pool Services and I have been living and working here for 3 years helping people with cleaning and maintaining their pools. During this time I have built up my experience in dealing with pools in the local area and would like to share my knowledge with you and hopefully help take some of the stress out of running your own pool. Whether you are a resident, holiday home owner or have a hotel with a pool it is a focal point in your life or business and, therefore, needs constant care and attention as it is no doubt a great asset.
Every pool is different, shapes, depths, in-ground, above ground etc…. my theories and methods are in a general capacity and may need to be fine tuned to each individual pool. Everything I write over the future months will be open to discussion in the forum and, if you have a topic that you would like to see reported here or have your own personal query, please feel free to email me at info@agua-pura.eu
In this article I have opted to offer you some guidelines into WATER BALANCING. Next time around we will look at how to organize and approach an ACID WASH, an area that you may be thinking of approaching before opening your pool this year, so if you have anything you would like to ask please just email.
Water balancing is not such a complicated exercise. It is simply the relationship between different chemical parameters. Your water is constantly changing, year round. Everything from weather to oils, to dirt, and cosmetics affect the water balance. You will probably not change the water in your pool for many years. Continuous filtration and disinfection removes contaminants which keep the water enjoyable but this does not balance your water. A pool that is "balanced" has proper levels of pH, Total Alkalinity and Calcium Hardness. It may also be defined as water that is neither corrosive nor scaling. How do we know when our water is over or under saturated? We use a good test kit (with fresh testing reagents ) to measure the chemical parameters of pH, alkalinity, and calcium hardness.
pH
pH is a measure of how acidic or basic the water is. pH is a logarithmic scale from 0-14, with 7 being neutral. Below 7 a substance is defined as being acidic, while levels above 7 are said to be basic or alkaline. Everything that enters your pool has a pH value. Ever heard of acid rain? This is rainfall with a very low pH. The human eye at a pH value of 7.35, is just slightly basic. This is, coincidentally, in range with proper 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 testing (recommended daily) of the water shows a pH value below 7.2 the water is in a corrosive (acidic) condition and you will need to add a base to bring the pH into a more basic range to prevent corrosion. Conversely, if the pH is above 7.8, we are in a scaling (basic) condition and must add an acid to bring down the pH to prevent the formation of scale.
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 "gunite" and concrete pools and 125-170ppm for painted, vinyl, and fiberglass pools. Levels should be tested weekly.
Calcium Hardness
When we speak of scale, we are talking about calcium carbonate which has come out of solution and deposited itself on surfaces. The test for Calcium Hardness is a measure of how "hard" or "soft" the water is testing. "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. If the levels are too low, the water is under-saturated. If under-saturated, the water will become aggressive. Such "soft-water" will actually corrode surfaces inside the pool which contain calcium and other minerals to maintain its hardness demand. If your Calcium Hardness levels are too high you can use TSP to lower the levels. Levels which are too low require the addition of calcium chloride. Recommended range for calcium hardness is 200-400ppm. Calcium Hardness levels should be tested monthly.
How often do I need to test the water?
I should say everyday, but I realise that's a bit much for most people. Commercial pools are required to check chlorine levels every hour and record their findings in a log, however the "backyard lifeguards" should check their pH and chlorine levels at least 2-3 times a week. Chlorine ideally should be fed continuously through a feeder device to maintain a consistent level, but again is not normally possible for private pool owners. Total Alkalinity and Calcium Hardness levels tend to fluctuate less, so weekly testing should be O.K.
What are the recommended levels?
· pH: 7.2 - 7.8
· Chlorine: 1.0 - 2.0 ppm
· Total Alkalinity: 80 - 120 ppm
· Calcium Hardness: 180 - 220 ppm, though some say 200 - 400.
· Cyanuric Acid: 25 - 50 ppm
· Total Dissolved Solids: 500 - 5000 ppm
This subject could continue through another couple of pages but I’ll leave you with the above for now and will return with part two in a few months. As I said earlier if you have a questions please send an email to info@agua-pura.eu
Thank you for taking the time to read my article and I hope you pay us a visit next month but don’t forget to browse through the website to find lots of other interesting facts and information on the costa de la luz.
