Section 1 - Maintenance Program Section 2 - Water Balance Section 3 - Disinfection, Sanitation, Oxidation Section 4 - How to Acid Wash Your Pool
MAINTENANCE PROGRAM These days it is not so hard to take care of a swimming pool. Twenty minutes a week is usually all it takes. Keeping up a routine maintenance schedule is your first line of defense against all pool-rated problems. A maintenance program consists of the following: Routinely testing your water and adding chemicals needed to balance the water. Routinely using your dip net to rid the pool of leaves and debris. Routinely using your brush to rid the pool of scale, algae etc. Routinely emptying your skimmer, pool cleaner bag, and pump baskets Routinely vacuuming the pool Routinely operate the filtration system and routinely clean the filter
So, your first question is probably "So what does routinely mean?" This is not an easy question to answer on a website. That is because the answer often depends on the season, where you live, the equipment and sanitation system you use, how much rain you get, the size of your pool, and the number of people using the pool. Routinely means that you find the right frequency for your conditions and then stick to that frequency. The average family living in Houston, Texas with a new WaterWorks of Texas (includes quality filtration equipment properly sized for the application) should use these guidelines and adjust to suit their particular situation:
Testing the water during the swimming season - Testing the water once a week is usually adequate. Check it more often if you are adding water or getting a lot of rain, if it was recently way out of balance, if it is extra hot, or the bather load is heavy. Remember to wait 24 hours after adding chemicals before re-testing.   Testing the water off-season - For pools that are not closed and winterized, we still need to keep the water balanced. Testing the water every 3-4 weeks is usually adequate. Check it more often if you are adding water or getting a lot of rain, or if it was recently way out of balance. Don't skip testing in the winter or you may subject your pool to etching, metal corrosion, staining, or scale. Remember to wait 24 hours after adding chemicals before re-testing.   Using the dip net - Most pools we build have automatic pool cleaners that pick up leaves, sand and debris off the bottom of the pool and owners rarely need to use their dip nets. It's good practice to check if using the net is needed when you check the chemicals and each day before anyone uses the pool during swim season.   Brushing and vacuuming the pool - Pools with automatic pool cleaners reduce the need for vacuuming and brushing but they are important and still need to be done periodically. Try alternating, brushing the pool one week and then vacuuming the next week. Vacuum more often if you notice dirt or fine debris on the bottom. Brush more often when the bather load is heavy. Brushing your pool is just like brushing your teeth and people notice when you skip.   Empty the skimmers, baskets and bag - You should check the skimmer baskets at least once a week, more often during the fall when leaves are blowing about. If the skimmer baskets get full, the filtration system is not able to do it's job. Be sure to share the suction between the main drains and the skimmers in case the skimmers do get full so you won't burn up your filtration pump and motor. Periodically check the baskets at the entry to the pumps. Make a point to clean them when you service the filter. Don't forget the pool cleaner bag. Keep it clean and it will last longer. Replace it promptly if torn or not closing properly.   Operate the filtration system - Most single family applications in the Houston area with our quality filtration equipment can be kept filtered and sanitized with 8 to12 hours a day of operation during the summer months and 4 to 8 hours a day during the winter months. Heavier use, warmer weather and contamination from dirt and leaves may necessitate longer operating periods.   Clean the filter - Cleaning the filter depends on the type you have. A good way to know when cleaning is needed is to monitor the pump pressure on the filtration tank. When the pressure rises 50-100 psi over the normal pressure, then it is time to clean the filter. If you have a DE filter, cleaning is done by backwashing and rinsing. Then add new DE to the system. If you have a sand filter, just backwash and rinse. If you have a cartridge filter, remove the filter and clean it with a recommended cleaning solution. Anytime you open the system, be sure the system is off and the pressure is bled off. Dab some pool seal lubricant on the o-rings before you close up the system. This helps prevent leaks and the seals will last longer.
WATER BALANCE Swimming pools need to maintain a certain “water balance” to protect the equipment and plaster and to insure swimmer comfort.  When the pH, total alkalinity and calcium hardness are within the recommend ranges the pool is considered to be balanced.
Chemical	Minimum	Ideal	Maximum
Chlorine	1.0 ppm	2.0-3.0 ppm	3.5 ppm
Cyanuric Acid	20 ppm	30-80 ppm	100 ppm
Bromine	2.0 ppm	2.5-4.0 ppm	5.0 ppm
pH	7.2	7.5	7.6
Alkalinity	70 ppm	80-140 ppm	150 ppm
Hardness	150 ppm	200-450 ppm	500 ppm
Total Dissolved Solids	400 ppm	1500-3000 ppm	3500 ppm
Copper	0 ppm	0 ppm	0.1 ppm
Iron	0 ppm	0 ppm	0.1 ppm
Many test kits on the market only test for chlorine, pH, and total alkalinity.  This is also true of the handy test strips. WaterWorks of Texas recommends that you select a test kit that can also test for calcium hardness and cyanuric acid. We don't have to check these two as often but they are very important. There are three main issues surrounding chemical testing.  The biggest is that chemical tests are performed too infrequently.  The second issue is that reagent (for the test kit) and test strips have a relatively short shelf life and should be replaced every season for seasonal pools and every six months for year-round pools.  The third issue deals with testing the sample itself.  You should never take a water sample near any return jet (the component that allows water to re-enter the pool after filtration), from any corner, or near the steps.  Pool water entering the pool via a return jet has just been filtered and cleaned.  Therefore, it will not accurately measure chemical ranges for the entire pool.  Conversely, pool water in corners and near steps is often somewhat stagnant, as circulation is poor in these areas.  You should obtain a sample from random areas in either the shallow or deep end of the pool, away from the return jets, and always reaching at least 18” below the surface of the water.   Water Balance > PH Solutions (including pool water) can be acidic or basic (alkaline).  PH is a value that indicates how acidic or basic a solution is.  The scale for pH ranges from 0-14.  The ideal pH for pools is 7.5; the acceptable range is 7.2  to 7.6.
Low pH will cause:		High pH will cause:
Etched plaster Corroded metals Stained plaster Eye and skin irritation Destruction of total alkalinity		Scale formation Cloudy water Short filter runs Eye and skin irritation Poor chlorine efficiency
To lower pH levels you add muriatic acid or a granular acid (pH minus)
To raise pH levels you add soda ash (pH plus)
Wear safety glasses and rubber gloves when using acid. Pour it directly into the deep end of the pool, taking care not to splash or to add too much in one spot.
Water Balance > TOTAL ALKALINITY  This is the measurement of the total amount of alkaline materials dissolved in the water.  It is said to be the buffering capacity of the water, the water resistance to change in pH.  Low or high total alkalinity can cause serious damage if left unchecked.
Low Total Alkalinity will cause:		High Total Alkalinity will cause:
Etched plaster Corroded metals Stained plaster pH bounce Eye and skin irritation		Scale formation Cloudy water Hard to change pH Eye and skin irritation Poor chlorine efficiency
To raise total alkalinity add sodium bicarbonate
To lower total alkalinity use muriatic acid or dry acid (pH minus)
Water Balance > CALCIUM HARDNESS Hardness is related to Alkalinity.  Hardness measures the amount of calcium, magnesium and manganese (which are three alkaline materials) that are present in the water.  The ideal range for hardness runs from about 150 ppm to 500 ppm. Of the three primary minerals measured under the category of Hardness, calcium is the most significant mineral.  Pool owners need to maintain a sufficient amount of calcium in their pool to achieve water chemistry.  Hardness only has to be tested approximately once per month  unless you are experiencing problems with dissolved metallic parts in your pool, discolored water, stains, or the formation of scale.  Periodically it is a good idea to carry a water sample down to the pool store and let them use the computer to professionally test the hardness level.
Problems resulting from low Hardness levels:
Metallic parts in your pool will dissolve (walls, floor, handrails, ladders, light fixtures, and equipment).  This could even lead to discolored water and stains on the pool walls and floor. Stained and etched concrete in concrete pools. Stained and etched plaster in gunite or shotcrete pools. Stained line in vinyl-liner pools. Blistering or delamination of fiberglass pools. Minimizes effectiveness of chlorine (or its alternative). Foam. Eye and skin irritation.
If your Hardness reading is too low (below 150 ppm), you will need to add Calcium Chloride.  This is typically packaged and sold as “Hardness Increaser,” “Hardness Up,” or “Hardness Plus.”
Problems resulting from high Hardness levels:
Cloudy water Scale formation on the pool walls, floor, plumbing and equipment. Overall poor filtration – primarily due to scale that is deposited inside the plumbing, which restricts water circulation. Minimizes effectiveness of chlorine (or its alternative). Eye and skin irritation.
If your Hardness level is too high (over 500 ppm), you will need to drain your pool, either partially or completely.  There is no chemical to lower the Hardness level.  Once refilled, it is then necessary to re-attain water chemistry.  If you typically have high Hardness levels due to the tap water in your region, you may have to add a metal sequestering agent to rid the water of excess harsh minerals.  If Hardness levels get too high over time, it is best to drain the pool – partially or completely – refill, and add a further dose of the Metal Sequestering Agent.
DISINFECTION, SANITATION & OXIDATION
Water by itself is rarely free of harsh minerals and other invaders, such as bacteria, living organism, ammonia, and other contaminates.  Other factors, such as climate and bather load, and poor water chemistry will add these invaders to your pool.  Certain chemicals have to be added to your pool in order to combat the undesired effects of these invaders.
Chlorine sanitizes, disinfectants, and oxidizes water.  By sanitizing, chlorine will kill all bacteria, living organisms, and other contaminates.  By disinfecting, chlorine will kill all potential disease carrying capabilities of these bacteria, living organisms, ammonia, and other contaminates in order to kill them.  More and more products are being introduced into the market as alternatives to chlorine, but chlorine is still the most widely used and the most effective.  Chlorine Tablets and Granular Chlorine are the most popular forms of chlorine.
The chlorine level must be closely watched, as it will fluctuate due to climate and bather load, and the constant introduction and reintroduction of bacteria, living organisms, ammonia, and other contaminates to your pool water.  Chlorine demand is the amount of chlorine needed to kill any of these invaders in your pool.  After this demand is met, the amount of chlorine remaining in the water to sanitize, disinfect, and oxidize is known as Free Chlorine. Chlorine will combine with bacteria, living organisms, ammonia, and other contaminates in order to kill them.  So, only a portion of the chlorine can continue to sanitize, disinfect, and oxidize the pool water while the remainder of the chlorine is occupied by an influx of these invaders.  This is why chlorine levels must be tested and adjusted often –2 to 3 times per week under normal conditions and use, and almost daily during periods of high heat and humidity, as well as after any rainfall, winds, or heavy bather loads.  This is also why you must shock your pool water regularly.
When chlorine-users shock their pools, they are really “superchlorinating” their pools.  It is necessary to add more chlorine to your pool because ammonia is present.  Chlorine will combine with but cannot kill ammonia.  The combination of chlorine and ammonia is called a Chloramine.  Chloramines will remain in the water, and will register as chlorine.  But they are unable to sanitize, disinfect, or oxidize the water because the ammonia has neutralized the chlorine.  Ammonia is commonly present in pool water from the environment, a build up of fertilizers that are carried by the wind, swimmer wastes and from some suntan lotions.  Ammonia can only be killed by shocking the pool.
Total chlorine is a measurement of both your Free Chlorine and the presence of Chloramines in your pool water.  To make it simple: Free Chlorine is good, and Chloramines are bad.  In order to maintain an ideal Free Chlorine reading of  2.0-3.0 ppm, you will need to regularly add chlorine (tablets or granular) to the pool.  In order to get rid of Chloramines, you will need to shock the pool.
Disinfection, Sanitation & Oxidation > POOL SHOCK
Calcium Hypochlorite, which is granular, is a chlorine-based shock compound that is often used.  It is best to dilute Calcium Hypochlorite in a bucket of water first, and then pour the diluted mixture in random areas of the pool.  It has a 65%-68% available chlorine.  Since it has such high available chlorine and dissolves slowly, the granules will not dilute before they fall to the pool floor.  If not diluted, these granules could bleach your pool floor.  Also because of the high chlorine content stay out of your pool for at least 8 hours after shocking with any chlorine-based shock compound.  As a guideline add 1 LB per 10,000 gallons of water under normal conditions and add 2 LBS per 10,000 gallons of water under extreme conditions.  If you live in region with high amounts of calcium in the water, which can be monitored by testing the Hardness level, use Lithium Hypochlorite-another chlorine-based shock.
Lithium Hypochlorite, which is granular, is a chlorine-based shock.  Lithium Hypochlorite has 35% available chlorine and dissolves quickly.  Again you should stay out of your pool for at least 8 hours after shocking with any chlorine-based shock compound.  As a guideline, add 2 LBS per 10,000 gallons of water under normal conditions and 3 LBS per 10,000 gallons of water under extreme conditions many chloramines, cloudy water or the presence of algae.
Potassium Peroxymonosulfate, which is sold as “non-chlorine shock”, is typically used with Bromine – the most popular alternative to chlorine.  Once added, non-chlorine shock will oxidize the ammonia, while at the same time reactivating the existing bromine in the water, allowing it to continue its job of sanitizing and disinfecting.  Perhaps the best benefit of using non-chlorine shock is that swimming can resume 15 minutes after its addition into the pool.  Non-chlorine shock can also be used in a chlorine pool, but it will only oxidize ammonia.  It will not reactivate the existing chlorine in the pool, so it is ineffective at sanitizing and disinfecting.  As a guideline, use 1 LB per 10,0000 gallons of water under normal conditions and 2 LBS per 10,000 gallons of water under extreme conditions-high bromamines (or chloramines), cloudy water, or the presence of algae.
How to Shock: Shocking a pool requires reading the instructions on the label.  The only way to add shock (and the only way to add any chemical) is either by diluting the shock in a bucket of water and then pouring it into the pool or by broadcasting the shock directly from the packaging and into the pool.  Here is a discussion of each:
When diluting, NEVER add water to the chemical.  Rather, ALWAYS add the chemical to the water.  You simply need to fill a bucket ½- ¾ full of water, pour the shock in the bucket of water (and only using 1 LB at a time), stir the shock with some sort of mixing stick to dilute the granules.  Then just walk around the pool, pouring the solution in random areas.
When broadcasting, you simply need to open the package of shock (1 LB at a time) and pour it directly into random areas of the pool.  Shock compounds used in broadcasting are commonly powder-like, so secure yourself on the pool deck and bend down close to the surface of the water before pouring.  If not, the wind could easily blow the shock out of the pool, or worse, into your face and eyes.  If this happens, flush your eyes with tap water (not chemically treated pool water) and seek emergency assistance.  At the same time, be careful not to get so close that you fall into your pool.
Regardless of the chosen shock compound, and regardless how it is added, it is recommended to add only 1 LB at a time, repeating the process (diluting or broadcasting) until the full dosage of shock is added to the pool.
Acid Washing Also called a drain & clean, an acid wash becomes necessary if the pool has turned into the "black lagoon". This may occur if the winterizing process is not done properly, or if the pool has been stagnant for a period of time so that algae has taken over. If you notice scaly, man-phibian creatures splashing around out back, it's probably time to drain & clean. Our general rule of thumb for determining the need for an acid wash is: if you can see the bottom of the pool (the floor) then you can bring it back with chemicals, labor and filtering. If the floor is not visible, the cost of the chemicals and labor will generally be greater than the acid wash charge, and take much, much longer. Also, extensive algae blooms will stain plastered pools, making an acid wash desirable. An acid wash is, put simply, purposeful stripping of a tiny layer of plaster, exposing fresh plaster beneath. Therefore, it is ill-advised to make it an annual custom, which will accelerate the need for replastering. Most plaster coats (sometimes called whitecoat or marcite) are in excess of 1/2", so a few careful acid washes should not hurt. Pools can also be bleach washed, pressure washed or treated with citric acid. You may also decide on an acid wash not because of swamp conditions, but just to bring out a brighter, whiter finish. Mineral stains and/or deposits, chlorine stains, even dirt stains...an acid wash is always a dramatic aesthetic improvement. If your pool has had years of algae blooms, and if your pool seems to grow algae overnight or just bloom very easily....changing the water and acid washing the surfaces algae sticks to can give you an algae free summer. Acid is a dangerous substance. Pool company personnel are specially trained in its application and wear protective clothing and breathing apparatus during the acid wash. To protect our environment, the acid/water waste should be neutralized  with soda ash prior to its being pumped to a safe location. If you decide to drain and clean your own pool, make sure that the hydrostatic relief plugs are pulled as soon as possible, and that the water is pumped to a distant location, or into a storm drain. You may also need to check with local water authorities for waste water discharge regulations. As you drain the pool, wash it down (scrub if necessary) to remove all algae and leaves. Bag up all leaves and debris in the pool's bottom. When the pool is clean and empty, you can begin to acid wash the plaster. Put on protective clothing and rubber boots, goggles and wear a breathing mask designed for acid fumes. Add 1 gallon acid to 1 gallon water in a flower watering can (Always add acid to water, never the other way around). Wet down the wall with a hose. Keep the hose running at all times, without a nozzle on it. Pour the acid/water mixture down the wall, from top to bottom, one 10 foot section at a time. Do not allow the acid to sit on the plaster for very long. Usually 30-60 seconds is long enough. Use an acid brush to scrub the surfaces and move the acid around. Rinse quickly and thoroughly. Make sure acid is rinsed completely, as it will continue to etch the plaster. Also try to prevent the acid from wearing a channel path from shallow end to deep end. This can create a worn stripe on the floor. If the 50/50 mixture isn't strong enough, you can increase the acid strength or the hang time (before rinsing),  or scrub harder. Usually pools are acid washed twice with the same strength mixture. Remember that you don't want to damage or "burn" the plaster. Don't rush the job and be safe. The fumes can be very strong. And very dangerous. It is advised that you pay a service company to perform this for you. If your pool is vinyl lined, acid is not used. Detergents, conditioners and good 'ol elbow grease will remove the "slime". The liner must then be "reset" with a vacuum to ensure proper fit during filling. Liner pools are normally not drained if it can be helped. There can be problems getting the liner to reset properly, and there is the danger of the walls collapsing. Complete drain & clean charges average $450. Higher costs may be seen for large amounts of debris in the pool, excessive neglect, or larger sized pools. Lower costs will be realized for clean or empty pools, or localized acid washings. If your water is from a well, you may elect to refill the pool with trucked - in water. Expect to pay $125.00 per 5,000 gallons. If you refill from the hose; water costs are a few dollars per thousand gallons. Contact your water authority to let them know you are filling the pool and they may not charge you for the sewer, only the water portion of the bill.