Calcium Scales: Causes, Clearing and Preventing White Flakes in a Saltwater Pool
Developing white flakes or calcium buildup in a non-saltwater pool is not common unless you are using a pool heater, or you have not been monitoring and balancing Calcium Hardness (CH), pH, TA, and other minerals levels, and these levels have gone extremely high forming calcium scales in your pool.
By nature, Calcium white flakes are common in saltwater swimming pools. This is because of the high temperature and pH in electrolytic chlorine generators and the use of calcium in the production of chlorine that is introduced in the pool.
White flakes or calcium buildups do not just come in saltwater pools overnight. But as a result of the gradual accumulation of calcium scales in the chlorine generator's salt cell plates.
When you start seeing white flakes coming into your pool through the inlet, it's too late because your salt cell plates have already been invaded by calcium buildups.
As the chlorine is produced in the electrolytic salt cell of a chlorine generator, a byproduct known as sodium hydroxide (NaOH) is formed, which by nature drives pH high in the salt cell and its environs.
Calcium scales or white flakes always form as a result of three things and they include:-
1) Heat,
2) High pH and
3) High minerals levels
All these three factors are in abundance in the salt cell and its environment.
When more of the scales accumulate on the plates in the salt cell forming calcium buildups, calcium flakes will be swept through the piping and soon you will start seeing white flakes coming out through the return jets or water inlets and settle at the bottom of your pool near the inlet or float on top of the water.
Calcium and other minerals including Phosphates, Silicates and Sulfates are among the causes of scales and cloudy pool water, and you need to take care by monitoring and controlling mineral levels in your pool as well on a regular basis.
Due to steady production of sodium hydroxide byproduct and the resulting high pH in the chlorine generator, the level of pH in your pool water will drift up more often, which may worsen your pool situation by encouraging more calcium scales that appear as white flakes in your pool.
That's why when using a Saltwater Chlorine Generator and a pool water heater, you have to stay on top of your water chemistry by measuring and adjusting pH and TA, Calcium Hardness and mineral levels to keep Calcium scaling at bay.
Calcium scales reduce lifespan of the entire chlorine generator, reduce chlorine production level and interfere with your water chemistry especially the pH and TA, chlorine and Calcium Hardness.
As such, since white flakes start form your chlorine generator, prevention of white calcium flakes in a saltwater pool starts by physically inspecting and cleaning your chlorine generator's salt cell plates regularly using muriatic acid.
When Do I Clean My Chlorine Generator's Salt Cell?
Top brand Chlorine Generators like Hayward Aquarite Saltwater Chlorine Generator comes with a reminder to inspect and clean your salt cell (Turbo Cell) every 500 hours.
If yours doesn't have a reminder, you don't need to wait until you start seeing white calcium flakes in your pool; there are early signs that you can check on frequently and clean your salt cells early enough to avoid seeing white flakes in your pool again:-
1). You know it's time to clean your salt cell when pH and Calcium levels in your saltwater pool are scaling high without raising them. Since you test your pool chemicals frequently if not daily, you will know when pH, TA, or CH levels drift up and take necessary measures to clean your salt cells and balance the chemicals appropriately.
2). Another good indicator to clean your salt cells is when your chlorine production level is low and will not raise your free chlorine to required levels easily. Calcium buildups reduces efficiency of chlorine generators and as a result less chlorine will be produced.
3). Also, it's a good maintenance practice to inspect and clean your Saltwater Chlorine Generator every 3 months or 500 hours of use, because either way, your salt cells will accumulate calcium buildup on the plates after sometime of use, a fact that most manufacturers of chlorine generators will not always remind you.
Mild Acid Wash: How Do I Clean My Electrolytic Chlorine Generator?
To clean your salt cell, you will need a garden hose, Muriatic acid and water. Before handling muritic acid, wear gloves and goggles to avoid injuries.
1). Turn off your pool circulation pump, turn off the power to saltwater chlorine generator control box if you have Hayward Aquarite, and disconnect the ionizer salt cell or Turbo Cell from the plumbing.
2). Inspect for any visible Calcium scales on the plates and wash them off using a garden hose. Don't mind If the garden hose doesn't remove all the calcium build ups or any visible rust as Muriatic acid wash will remove them all.
3). Add 1 gallon of water in a bucket and add 1 quarter of muritic acid in the water inside the bucket (4:1 water to acid) to form a mild muriatic acid.
4). If you have Hayward Turbo Cell, don't dip it in the acid solution but place the T-Cell in the cleaning stand so that it is in a vertical position, then pour muriatic acid solution slowly through the Cells to fill it with acid solution and leave 15 minutes or until the bubbles settle, to remove tough calcium buildups and any rust visible on the salt cell then pour out the acid back to the bucket. If you use ionizer salt cell, dip the salt cell in the mild muriatic acid for 15 minutes or until the bubbles settle and remove the salt cell. Repeat the process of mild acid wash until you can see no more buildups or stains.
5). Rinse the salt cell again with a hose pipe to clean off loose buildups and rust after the mild muriatic acid wash, and then reinstall the salt cell into the plumbing and put the pump back on.
How to Clear White Calcium Flakes from the Pool
To clear white flakes from your pool, you should have already cleaned your salt cell and then follow these next steps.
1). Since white flakes are simply calcium buildups, this means that your calcium hardness (CH) level is extremely higher than the recommended level of 250 ppm to 350 ppm. To lower your CH level, you will have to drain and refill a portion of your pool water with fresh water, which is the only practical way you can lower your calcium levels.
2). Lower and balance your pH and TA levels between 7.2-7.4 and 80-120ppm respectively using muriatic acid. Since chlorine generator will definitely raise your pool pH, which is an ingredient in developing calcium buildups, lowering your pH in your pool will reduce the calcium buildups in your water.
3). If lowering calcium and pH level do not bring expected results, you will have to use a calcium scale remover and inhibitor like Orenda SC-1000. You may need regular doses of scale control chemical, but that is not a scapegoat to cleaning your salt cell regularly.