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This page is to provide you with helpful information on various aspects of swimming pool care and maintenance. We hope that the information we have provided will be useful to you and help give you a better understanding of your pool. If you don't find the answer to your question(s) here, please feel free to Contact us!

Why Is My Pool Green?

A green pool may be caused by a number of things. Most common is:

(1) No chlorine exists in the water. Without chlorine present, algae thrives and leads to an “algae bloom”. It will be necessary to add more than the usual amount of chlorine to shock it back to ideal conditions. In addition, it is recommended that you run your filter pump 24/7 until pool water is returned to ideal conditions. After heavily shocking (adding granular chlorine) to your pool, it may cloud briefly, but you should begin to see the green changing to blue. The additional filtration time will take care of any cloudiness usually.

You should also check the pH and the Total Alkalinity. An imbalance in these two factors, especially if they are too low, will create an ideal environment for algae growth. Ideal level, in a gunite pool, for pH, is 7.4. A range of 7.2-7.6 is acceptable. For the Total Alkalinity, in a gunite pool, it is recommended you maintain it between 80-120 ppm.

(2) Filter time may not be sufficient. Especially during a hot Texas summer, it is recommended to run your filter pump a minimum of 8 hours daily, perhaps as much as 10-12 hours in cases of heavy bather load. Even during the winter, filter pump should be run a minimum 8 hours daily. Many experts claim that 4-6 hours is enough time for all the water in an average residential pool to be filtered once, but heavy use and high temperatures dictate running the pump more.

(3) Filter may be compromised. If it hasn’t been backwashed and/or cleaned recently, the circulation may be rather poor. In the case of a Diatomaceous Earth filter, grids or manifold may be damaged, allowing the filter media to return to the pool. In a sand filter, sand may be old and packed down, and not stirring around while being backwashed. Cartridges may have reached their capacity and need to be cleaned or replaced.

(4) In some cases, the cyanuric acid level is so high that it makes it difficult to maintain balanced water. Total dissolved solids (TDS) can also cause balancing problems. In both cases, it will be necessary to drain much of the water from pool and replace it. Don’t forget to balance the water afterwards.

How do I backwash my diatomaceous earth pool filter?

A diatomaceous earth filter should be backwashed at least every three weeks. Proper backwash procedure is as follows:

Turn pump off. Put valve in backwash mode. (If you have a push/pull valve, backwash is in the up position.) If you have a flexible backwash hose attached, unroll and direct to the desired area. Turn pump on and allow to run for at least 30 seconds, or until water is clear. Turn pump off. Return valve to filter mode or rinse mode. (If you have push/pull valve, filter mode is in the down position.) Turn pump on and allow to run for 15 seconds. Repeat these steps at least three times, and more if water still is not clear. Don’t forget to recharge your filter with the proper amount of diatomaceous earth. For your convenience, I have listed quantities of diatomaceous earth which should be added.

  • 24 square feet filter, use 3 lbs. diatomaceous earth
  • 36 square feet filter, use 5 lbs. diatomaceous earth
  • 48 square feet filter, use 6 lbs. diatomaceous earth
  • 60 square feet filter, use 7 lbs. diatomaceous earth
  • 72 square feet filter, use 8 lbs. diatomaceous earth

Backwashing regularly will extend the life of your filter components. But even still, every six months, filter should be opened up and disassembled for a more thorough clean. Do not rely only on reading changes on filter pressure gauge. While cleaning grids, check carefully for torn fabric, broken ribs, and cracked necks. Also check that the standpipe o-ring is still in place. Make sure there are no cracks in filter manifold. Replace any damaged parts to avoid having diatomaceous earth returning to your pool. At times, you may run into problems re-assembling filter assembly.

What should I do when the temperature is below freezing?

When the outdoor air temperature reaches 32 degrees or lower, costly freeze damage can occur. These steps should be followed to help prevent any damage to your pool and/or equipment:

  • Run filtration pump and all auxiliary pumps continuously (pool cleaner pump does not need to run). If functioning properly, your freeze guard should run the pump automatically until temperatures rise above freezing. Note: Direct sunlight on your freeze guard may “trick” it into functioning as if the temperature is above freezing thereby turning off your pump. If this happens, reactivate the pump manually and remove the timer trippers or switch the computer controller to “service” and turn the pumps on. The pumps WILL NOT turn off automatically in service mode.
  • Break up ice on the pool and spa surfaces to keep the skimmers and skimmer doors free from ice. Carefully remove skimmer doors if it is not possible to keep them free of ice. Use caution to avoid damaging the skimmers.
  • Maintain proper pool water level at all times (at the middle of the tile line). If the water level drops too low, the pump will draw in air through the skimmers which increases the risk of equipment freeze damage.
  • NEVER backwash during extremely cold conditions. Filter pressure gauges can freeze, resulting in inaccurate readings.
  • DO NOT use heater during extreme cold unless it has been constantly running prior to the drop in temperature.
  • Adjust pool and spa jets upwards to reduce surface freezing