How can pool owners determine whether they will be happier with a saltwater pool?
The low saline water in salt pools—about one-tenth the salinity of ocean water—feels softer and more soothing to a bather’s eyes, nose and skin. If customers are sensitive to traditional pool chemicals, they may prefer saltwater.
Saltwater pools can also require less maintenance, so they can be ideal for frequent travellers. The ECG constantly converts saltwater to chlorine, so there is no need to routinely purchase, transport, store, handle and add chlorine. It also keeps the levels of chlorine more consistent, so there are fewer peaks and valleys when algae typically gain a foothold.
If a customer decides to convert their pool to saltwater sanitation, here are a few things to keep in mind:
- The ECG should be selected according to pool size and bather load, rather than pool size alone. For example, if a customer has a 75,700-L (20,000-gal) pool that is heavily used during the season, an ECG sized according to a 133,500- to 141,400-L (30,000- to 40,000-gal) pool may be needed. This will ensure sufficient chlorine production for the actual usage. Keep in mind, the ECG should be installed according to manufacturer instructions, ensuring it is properly ground and bonded.
- Add treatment products to protect the pool against staining and scale, but make sure these products are specifically designed for saltwater pools. The interior of the ECG has extreme pH ranges (up to 14 on the cathode and as low as one on the anode), high chlorine levels (exceeding 50 ppm) and relatively high temperatures, which can exceed 49 C (120 F). In these harsh conditions, many conventional pool water chemicals designed to prevent staining, scaling and corrosion break down into compounds like orthophosphates, which are nutrients for algae and contribute to scale formation. The products used in saltwater pools need to work within the harsh conditions of the ECG and should not contain ingredients like sulfates (SO2−4) or phosphorous-based sequestrants, which can contribute to scale formation on cell plates.
- Use high-quality salt (as pure as possible). All salts are not created equally. Depending on its type, salt may contain naturally-occurring contaminants that can damage a pool. Some salts contain organic contaminants, which can cause cloudy water and increase chlorine demand, while other types may contain varying amounts of inorganic contaminants, such as manganese (Mn), copper (Cu), iron (Fe), nitrates (NO−3), silicates (SiO44−), sulfates, calcium (Ca) and metals. Many of these contaminants can affect water clarity, dissolution rate, stain and scale potential and other important water balance factors.
- Use salt specifically designed for pool water sanitation and check with suppliers to confirm the source of the type of salt being purchased. Mechanically evaporated salt is best for saltwater pools. Solar salt can cause increased chlorine demand due to organic contaminants, while mined rock salt should never be used as it contains impurities at higher levels than accepted.
- When adding salt, use enough to reach the midpoint of the range recommended by the ECG manufacturer. It is better to add too little salt than too much, as more salt can always be added if needed. If too much salt is added, the pool will need to be partially drained and fresh water added to dilute the salt level. Always add salt to the pool’s deep end, while the pump is running, and brush until dissolved.
Customer advice
Whether customers own an existing saltwater pool or recently converted, it is important to teach them to test and balance their pool water regularly. Saltwater pools require less maintenance than traditional pools, but they are not maintenance-free.
For residential pools, it is recommended pH and chlorine levels are tested weekly, while total alkalinity, calcium hardness, stabilizer/CYA and metals (especially if they occur in the water source) are tested monthly. Salinity can also be tested monthly to ensure it is maintained at the required level.
Proper opening techniques in the spring, followed by proper maintenance throughout the season, will help ensure problem-free pools and happy customers.
Bob Harper is general manager of pool products at Pristiva, a Compass Minerals company. He has more than 25 years of experience in the pool and spa industry and is an expert in saltwater pool systems. He can be reached via e-mail at harperb@pristiva.net.
