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SYMPTOM: Cloudy/milky Water. There are four possible causes - your test kit will give you the best idea as to which is the most likely.

SYMPTOM: Cloudy/green Water.

SYMPTOM: Rust red Water.


SYMPTOM: Stinging eyes, sore throat and skin irritation. There are three possible causes - use your test kit to see which is the most probable.

SYMPTOM: Blond or tinted hair turns green.

SYMPTOM: Allergy to chlorine.


SYMPTOM: Chlorine has been added to the water, but there is no reading on the test kit.

SYMPTOM: The chlorine level is difficult to maintain. There are three possible causes.


SYMPTOM: Tendency for the pH to remain low (below 7.2).

SYMPTOM: Tendency for the pH to be permanently high (above 7.6).

SYMPTOM: pH values are erratic and fluctuate.

SYMPTOM: pH is locked.

SYMPTOM: Tendency for the alkalinity to be too low.


SYMPTOM: Loss of grouting in mosaic/tiled pools, or sharp edges around tiles. There are two possible factors at work here:

SYMPTOM: Pool surfaces feel rough and scaly.

SYMPTOM: Pool surfaces feel slippery.

SYMPTOM: Tide mark on pool wall at water line.


SYMPTOM: Ineffective filtration in sand filters.

SYMPTOM: Ineffective filtration in cartridge filters.

1.  What can you do to help make your pool safe?

Here are some safety tips:

2.  What should you know about during the pool construction process?

What should you know about during the swimming pool construction process?

First of all, the contract for your swimming pool construction should call for the work to be performed in accordance with all applicable building codes. As a general rule, a building permit is required whenever structural work is involved or when the basic living area of a home will be changed. Swimming pool construction falls into these categories. The contractor should obtain the necessary building permits, and this arrangement should be spelled out in your contract. Otherwise, you may be held legally responsible for failure to obtain the required permits.

After you've signed a contract, and even after work has already begun, your contractor may offer suggestions that will change your original ideas for the work. If you have discussed added work, substitutions of materials or equipment, or changes in the completion date, make sure that clearly worded and signed "change orders" reflect this.

In most cases, you will be living in your home and using your yard while work is ongoing. Be aware of the many inconveniences that may occur. To gain access to your yard for construction of a pool, the contractor may have to remove or damage some existing landscaping or fencing. Before work begins, ask your contractor what inconveniences will occur, then plan for them.

During the construction process, keep a job file of all documents related to your project, including the contract and any change orders, plans and specifications, bills and invoices, cancelled checks, lien releases, notes and correspondence, and photos of the job in progress.

It is also a good idea to keep a record of sub-contractors, the dates they were on the job and the work they performed, and to document material deliveries.

3.  How can you save money on energy and costs with outdoor swimming pools?

Here are some energy management ideas and improvements that can be implemented with outdoor swimming pools to save money.

Covers for swimming pools

Swimming pools lose energy in a variety of ways, but evaporation is by far the largest source of energy loss for swimming pools. When compared to evaporation, all other losses are small.

Since evaporation is the major source of heat loss for swimming pools, to minimize evaporation, one must cover the water. Covering swimming pools when not in use is the single most effective way of reducing heating costs. Savings of 50-70% are possible.

Covers also provide many other benefits besides saving energy. They conserve make-up water by 30-50% and can reduce chemical consumption. Cleaning time is cut by preventing dirt and other debris from entering the water.

Wind breaks

One item that can greatly increase evaporation from outdoor swimming pools is wind blowing over the water. A 7 mph wind at the surface of the pool can increase energy consumption by 300%. Adding trees, shrubs, fences, or other wind break material can significantly lower the heat loss while it's open.

Swimming pool covers are great at stopping evaporation when the pool is closed, but can't do anything to cut evaporation when it's open.

The windbreak needs to be high enough and close enough to the pool that it doesn't create turbulence over the water and increase evaporation, but try not to block the sun from shining on it.

Solar heating systems

One of the most cost-effective uses of solar energy is to heat swimming pools. Swimming pools require low temperature heat, which is where solar collectors are most efficient.

You can use either unglazed or glazed collectors to heat outdoor swimming pools, however, unglazed collectors are most commonly used on outdoor pools. If your pool is operated year around and located in a cold climate region, the unglazed systems will not provide much heat in the winter, but may be more cost-effective overall because of their lower initial cost.

Glazed systems are more expensive, because they usually have black chrome-plated copper absorber plates, require the use of a non-freezing transfer fluid and a heat exchanger to transfer the solar heat to the swimming water.

Unglazed systems are usually made of a black plastic or rubber material and the water is circulated directly through the collectors. Neither system requires a storage tank. The pool serves as the storage tank.

Solar heating systems can provide up to 100% of your pool heating needs. They are also much simpler to install than are other forms of solar systems. The combination of a solar pool heating system and the use of a cover at night can greatly extend the length of your swimming season with minimal operating costs.


High efficiency heaters

If you plan to purchase a conventional pool heating system, shop around for a high efficiency pool heater. High efficiency gas heating systems are available with steady state efficiencies as high as 97%. Electric heat pump pool heaters are also available with coefficients of performance (COPs) in the 6.0-8.0 range when operated in warm weather. A COP of 6.0 is 600% more efficient than an electric resistance heater.

Efficient pumps/motors

Using properly sized energy-efficient pumps and motors when replacing older pumps and motors, or when designing new swimming pools, can significantly lower the electrical consumption of pool operating costs. Motors use many times their initial cost in electrical consumption over their life and can often consume several times their cost in the first year alone. The energy savings from an energy efficient motor can pay for itself in a very short time.

Efficient pool lighting

Replace inefficient incandescent lamps with high efficiency compact fluorescents. They consume 1/2 to 1/3 the amount of electricity and last 10 times as long as standard incandescent lamps. Replace standard fluorescent ballasts and lamps with electronic ballasts and T-8 lamps. They will reduce consumption by 30%.

The initial cost of energy efficient lighting is more, but the combination of the energy savings and labor savings on replacement will far offset that initial cost in most cases where lights are on for several hours per day or night.

Outdoor areas can be lit with high intensity discharge (HID) lamps. They offer high efficiency and high output. Install motion detectors in areas like shower/dressing areas and rest rooms or on security lighting. They will not only save energy, but will startle would-be intruders.

Water efficiency

Reduce water heating costs in the shower area by lowering shower temperatures to 95. It will not only lower energy costs, but will shorten the amount of time people spend under the shower producing further savings.

Install low-flow showerheads and automatic shut-off valves on showers to reduce water consumption and conserve energy.

Insulate the shower water heater to further reduce water heating costs.

Efficient operation

Consider carefully the temperature that you keep the water. Each degree rise in the temperature can cost you an additional 10%. The National Swimming Pool Foundation recommends 78-80 for active swimming and 82-84 for general use.

It's a myth that it takes more energy to heat swimming pools up when you turn the temperature down than you save by lowering the temperature or by turning off the heater. Turn the temperature down, or turn off the heater whenever the pool will not be used for several days. Experiment to determine how long it takes to heat it back up. Lowering the temperature and raising it back up again always saves more energy than keeping it at a constant temperature.

Keep all the intake grates clear of foreign debris. Clogged drains require the pump to work harder.

Don't backwash your filter more frequently than necessary. Backwashing too frequently wastes water, while not backwashing wastes energy by requiring the pump to work harder.

For residential swimming pools, reduce filtration time to 6 hours/day. If the water doesn't appear clean, increase the time in half-hour increments until you get the desired results. You can automate this by installing a time clock for daily pump operation.

Tune up your heater annually. A properly maintained pool heater is more efficient.

Pool heater information

Here are some common pool heater questions. Scroll down for the answers.


Cost of pool heating

The chart below shows costs of heating pools in different parts of the country to different temperatures. The figures are based on a 1000 square foot outdoor pool heated with an 80% efficient natural gas heater at $.50 per therm. The dramatic cost difference for using a cover is also shown. It's assumed the pool is uncovered for 8 hours per day.

Location Season Temperature
78 80 82
Miami 1/1-12/31 $1335 $1780 $2250
w/cover 1/1-12/31 $260 $365 $500
Phoenix 3/1-10/31 $865 $1110 $1385
w/ cover 3/1-10/31 $60 $105 $160
Dallas 4/1-10/31 $945 $1200 $1535
w/ cover 4/1-10/31 $115 $175 $255
Atlanta 4/1-10/31 $1065 $1405 $1800
w/ cover 4/1-10/31 $200 $265 $370
Los Angeles 5/1-10/31 $1165 $1485 $1815
w/ cover 5/1-10/31 $105 $190 $295
Kansas City 5/1-10/31 $896 $1170 $1490
w/ cover 5/1-10/31 $180 $260 $340
New York 5/1-9/30 $905 $1190 $1490
w/ cover 5/1-9/30 $130 $185 $250
Chicago 5/1-9/30 $1013 $1295 $1585
w/ cover 5/1-9/30 $135 $185 $240
Denver 5/1-8/31 $1292 $1560 $1835
w/ cover 5/1-8/31 $110 $145 $225
Boston 5/1-8/31 $1070 $1310 $1565
w/ cover 5/1-8/31 $145 $205 $288
Minneapolis 6/1-9/30 $832 $1110 $1360
w/ cover 6/1-9/30 $120 $155 $240
San Fran 6/1-8/31 $975 $1160 $1355
w/ cover 6/1-8/31 $120 $200 $295
Seattle 6/1-8/31 $953 $1115 $1285
w/ cover 6/1-8/31 $190 $265 $345

Pool heater size

Pool heaters are mainly sized according to the surface area of the pool and the difference between the water and average air temperatures. One method uses the following procedure:

  1. Determine the desired swimming temperature.

  2. Determine the average temperature for the coldest month of use.

  3. Subtract the average temperature from the desired temperature to get the temperature rise needed.

  4. Calculate the pool surface area.

  5. Use the following formula to determine the Btu/Hr output requirement of the heater.
    PoolArea x TemperatureRise x 12

This formula is based on 1 to 1-1/4 F temperature rise per hour and a 3-1/2 mph average wind at the pool surface. For a 1-1/2 F rise multiply by 1.5. For a 2F rise multiply by 2.0.

The heating load is also affected by other factors such as wind exposure, humidity levels and cool night temperatures. Pools located in areas with higher average wind speeds at the pool surface, lower humidity, and cool nights will require a larger heater.

This calculation will give you an approximate size. You should have a trained professional perform a proper sizing analysis for your specific pool.

Gas pool heaters

Today the most popular method of heating pools is the gas-fired pool heater. Heaters are built for either natural gas or propane.

Gas appliances have become increasingly more efficient in recent years. With innovations in hydraulics, heat exchanger technology, forced draft combustion systems, and pilot-less ignitions, efficiency has almost doubled in recent years. High efficiency pool heaters are now available that are 89-95% efficient.

Heater efficiency is the ratio of usable output to energy input. For example, with a 80% efficient heating appliance, there is $80 worth of useful heat for every $100 of fuel bought. 20% of the fuel is wasted.

Heat pump pool heaters

An emerging method of heating pools is the heat pump pool heater. A heat pump's efficiency is dependent on the outside temperature and since pools are usually used during warm and mild weather, heat pumps are a very efficient method of heating pools.

Heat pumps do not generate heat, they simply capture it and move it from one place to another. Below is a diagram that shows how heat pumps operate.

How efficient is a heat pump? That's not an easy question to answer. Heat pumps don't have a simple efficiency number to work with. Their efficiency is measured by Coefficient of Performance (COP).

Just like other heating options, heat pumps can have low efficiencies or high efficiencies. Their COP can range from 3.0-7.0. The higher the number the more efficient the heat pump. What this means is that for every unit of electricity that you put in to run the compressor, you get 3-7 units of heat out of the heat pump. These COPs are usually determined by testing the unit with an outdoor air temperature of 80F and a water temperature of 80F. But there is no standard test, so you should be aware of this. The higher efficiency units usually use scroll compressors versus the reciprocal compressors of the standard units.

Buying a pool heater

Efficiency is one consideration in buying a pool heater, but you should also consider the reputation of the manufacturer and/or dealer who will install your heater. Get some references of satisfied customers and call the Better Business Bureau if you don't have anything to go on. Also be sure to ask for and read all warranties before making your decision.

Pool heater money saving tips

Regardless of what pool heater you buy, here are some tips to help you reduce your heating costs.

Pool covers?

Why do people use pool covers?

Pools lose energy in a variety of ways, but evaporation is by far the largest source of energy loss for swimming pools. When compared to evaporation, all other losses are small.

Since evaporation is the major source of heat loss for all swimming pools, to minimize evaporation one must cover the pool. Covering the water with a pool cover when it is not in use is the single most effective means of reducing heating costs. Savings of 50-70% are possible.

Types of pool covers

Technically, all you really need is a large sheet of plastic. Plastic meets the requirement of being a vapor barrier. But a large sheet of plastic that you get from the lumber store is probably not your best choice. It will be very difficult to handle and store, it tears easily, and sunlight will deteriorate it rapidly. You can use it, but it will be very inconvenient and will only last 1 to 2 seasons max.

There are a number of manufacturers that produce covers designed specifically for swimming pools (see Pool Gear Plus's solar covers page for information about ordering a pool cover online). They can be made of different materials, such as UV stabilized polyethylene, polypropylene, or vinyl. They can be transparent or opaque. They can be light colored or dark colored.

One of the lowest cost pool covers made specifically for swimming pools is the bubble cover (some call them solar covers). They are similar to bubble packing material except that they use a thicker grade of plastic and have UV inhibitors, etc.

Vinyl covers are a heavier material and have a longer life expectancy. You can also get insulated vinyl covers with a thin layer of flexible insulation sandwiched between two layers of vinyl.

Outdoor pools gain heat from the sun, absorbing 75-85% of the solar energy striking the water's surface. This is an important contribution to its heating needs.

So when considering a pool cover, note that a cover will also decrease the solar gain contribution to some extent, depending on the type of pool cover used. A transparent bubble cover may reduce solar energy absorption by 5-15%, and a completely opaque cover by 20-40%.

Methods of using pool covers

There are several ways of covering your pool. The simplest and lowest first cost method is to manually pull the cover on and off, fold it, and place it somewhere out of the way. If you are paying someone to do this, you need to consider that cost in your economic evaluation. You can also purchase a pool cover reel that can be used to manually roll the pool cover up. The reel, usually on wheels, can then be rolled out of the way.

Semi-automatic covers use a motor driven reel system. They use electrical power to roll and unroll the cover, but usually require someone to pull on the cover when unrolling, or guide the cover onto the reel when rolling the cover up. They can be built into the deck surrounding the pool, or can use reels on carts.

Automatic covers have permanently mounted reels that automatically cover and uncover the pool at the push of a button. They are also the most expensive first cost option. But you have to weigh the cost of labor for the manual and semi-automatic covers to determine which route is best for your particular situation.

Some pool covers are fitted into tracks along the sides of the pool. This prevents anything or anybody from getting into the water. They even support the weight of several people. If liability is a concern, these are a good option to explore. They can be run manually, semi-automatically, or automatically.

When to use pool covers

For pools which are open all day, a cover should be placed over the water as soon as it closes, and taken off just before it opens for the day.

For pools which are not in use during daylight hours, the effectiveness of a pool cover will depend on whether the evaporation and other losses prevented by the cover exceed the solar gain reduction caused by the cover. This balance is affected by the type of cover and the climate. In dry and/or windy conditions the evaporation rate increases, and it is generally beneficial to have a transparent or bubble cover on during daylight hours. In warm, humid conditions the evaporation rate decreases, and it may be more beneficial to leave the cover off during the daytime.

Other benefits of pool covers

Pool covers also provide many other benefits beside the tremendous energy savings. They conserve water by reducing the amount of make-up water needed by 30-50%. They can reduce chemical consumption by 35-60%. They also cut cleaning time by keeping dirt and other debris out of the water.

It is highly recommended that the first step to cutting energy loss be the evaluation of the economics of using a swimming pool cover. (To clarify, we are not talking about pool covers that you use to cover the pool in the off season or mesh safety covers. Those do not save energy. We are talking about plastic or vinyl pool covers that you use during the swimming season when it is not in use.)

Pool Size AG 48" 52"
12' RD AG 2975 3398
15' RD AG 4646 5310
18' RD AG 7646 8602
21' RD AG 9106 10408
24' RD AG 11895 13594
27' RD AG 15054 17205
30' RD AG 18585 21240
33' RD AG 22488 25700
12' x 24' OVAL AG 5948 6797
15' x 30' OVAL AG 9293 10620
18' x 33' OVAL AG 12267 14019
21' x 41' OVAL AG 24250
12' x 24' 7600 8600 9700 10800
14' x 28' 10300 11800 13200 14700
15' x 30' 11800 13500 15200 16900
16' x 32' 13400 15400 17300 19200
18' x 36' 17000 19400 21900 24300
19' x 38' 19000 21700 24400 27100
20' x 40' 21000 24000 27000 30000
22' x 44' 25400 29000 32700 36300
25' x 45' 29531 33750 37968 42187
25' x 50' 32800 37500 42200 46900
30' x 50' 39375 45000 50525 56250