Changing saltwater pool water every 2 years?

[ps_pool]

Just bought a pool home in Palm Springs, CA, and our pool service tech is suggesting that we drain/replace the water every 2 years (and coincidentally needs doing this summer). It's a saltwater system, and so far the water has been perfect by all measurements.

This seems really extravagant, and I cannot find any references on it.

Would appreciate any thoughts/recommendations.

 

[JasonLion]

Welcome to TFP!

There are some specific problems that occasionally require water replacement. If you don't have one of those specific problems then there isn't any point in replacing your water. There are some areas of the country where one or another of these issues come up frequently, for example people in Arizona often have problems with high calcium levels. But even then it is well worth trying to put off water replacement as long as you can, rather than doing it on a regular schedule.

 

[ps_pool]

Thanks, that is the general sense I am getting through the research so far. Calcium build-up is a problem in the desert, so we'll keep an eye on that.

Thanks again.

 

[Butterfly]

Welcome to TFP


Our gurus are wonderful!

 

[Guest]

very high calcium levels would be the main reason, as long as the fill water has a lower calcium hardness than the water in the pool.

 

[mas985]

very high calcium levels would be the main reason, as long as the fill water has a lower calcium hardness than the water in the pool.

That's been my reason for refills. So far, I have had to replace close to 50% of the pool water each year due to high calcium (>500 ppm). Last year I had a little scaling because it got so high. The city is planning on large scale water softners but I'm not sure if that will help much since during the hot months most of the water comes from wells.

 

[Poolsean]

You should be able to offset the high calcium somewhat by running a lower pH and TA level.

Perhaps I missed which model system you have, but with the Pool Pilot, you can also adjust the reverse polarity more frequently to help keep the scale off.

 

[Strannik]

very high calcium levels would be the main reason, as long as the fill water has a lower calcium hardness than the water in the pool.

That's been my reason for refills. So far, I have had to replace close to 50% of the pool water each year due to high calcium (>500 ppm). Last year I had a little scaling because it got so high. The city is planning on large scale water softners but I'm not sure if that will help much since during the hot months most of the water comes from wells.

I don't know how often it rains in CA, but one thing you should probably consider is getting a water tank, to catch rainwater and then use it on your pool.

 

[chem geek]

I don't know how often it rains in CA, but one thing you should probably consider is getting a water tank, to catch rainwater and then use it on your pool.

Palm Springs is in the desert area of California with minimal rainfall as shown here. Some areas of California get plenty of rain, especially in Northern California. Where I live, just north of San Francisco, we get about 3 feet of rainfall mostly over the winter season (Oct - Apr, esp. Nov - Mar) so I can readily dilute the pool (S.F. itself gets less rain; about 20"), but for those who live in Southern California such as Los Angeles, they get about 1 foot of rain (see here).

Also, this link shows the evaporation rate over the year which in many areas is mostly over the extended summer season (though in Palm Springs would still have substantial evaporation in the winter). Palm Springs is in the desert region where the evaporation rate is 100" per year which is nearly the amount for two full pool water replacements. According to this water quality report for Palm Springs in 2006, the groundwater source has around 65 ppm calcium which is about 160 Calcium Hardness (as ppm CaCO₃) so the evaporation and fill water replacement would increase CH by over 300 ppm per year IF the water was mostly groundwater (the surface water is far lower in calcium).

The most effective way to keep the evaporation down and therefore the CH more stable is to use a pool cover and this will also save on water usage (limiting evaporation limits the amount of refill).

Richard

 

[Strannik]

In that case they are lucky they have ground water. Our councils which don't have ground water introduced various levels of water restrictions, here is the example for my council:

From 23 November existing pool owners who plan to continue using town water to top up or fill pools must have:

* a rainwater tank or a downpipe rainwater diverter installed and connected to the swimming pool or spa
* three of the following four measures in their home
o a four star-rated washing machine
o dual flush toilets throughout the home
o a pool cover
o all indoor water appliances (showers and tap heads) are water-efficient.

In addition, all available water must be used from the rainwater tank or downpipe rainwater diverter to top up a swimming pool or spa before any water is used from the reticulated (town) water supply system for that purpose.

From 23 November 2007:

Topping up existing swimming pools can only occur between 4 pm and 7 pm for:

Odd numbered properties

Tuesday, Thursday and Saturday

Even numbered and un-numbered properties

Wednesday, Friday and Sunday