These water balance tips for SWGs will help you maintain your salt pool with the fewest problems. If you follow them you will probably never need to SLAM (or shock) your pool and you will maintain a more stable pH then if you go outside of these limits. They might not agree exactly with the manufacturer’s recommended levels but they WORK and will help you have a Trouble Free Salt Pool!
First step is to adjust salt to the manufacturer’s recommended range. This is usually around 3200 ppm but some models need a higher level. Check your manual to ensure you do not add too much.
Second, adjust CYA to between 70 and 80. The biggest mistake that many SWG owners make is NOT having enough CYA in the water! This can create a lot of problems like high acid demand, algae outbreaks, cloudy water, or early cell failure.
Adjust the SWG percentage setting or pump run time so your FC level stays between 5-7 ppm (assuming CYA is 70-80). Early evening is the best time to measure FC level when attempting to dial in your SWG percentage. If the SWG is running at 100% and it still does not maintain a high enough FC level, you need to increase your pump run time.
There are some advantages to running the SWG during the day while the sun is shining on the pool. Unless there is some other reason not to run the pump during the day, like time of day electric rates that are higher during the day, program the pump to run while the sun is shining on the pool.
Adjust your total alkalinity to 60-80 ppm. Maintain your pH between 7.2-7.8 and not any lower. Add muriatic acid as needed to lower it back to 7.2 – 7.5. Careful monitoring of these parameters will prevent scale buildup and promote long salt cell life.
Adjust calcium hardness to 350 ppm for plaster and fiberglass. Vinyl pools are OK if the CH is at 50 ppm or higher. In any case try to keep below 400 ppm or you will have to keep close watch on your pH to prevent scale buildup. Test your fill water for CH. If your fill water has high CH, your CH will rise over time. Maintaining your pH as recommended above will prevent scaling. High pH leads to scaling, period! Keep pH below 8.0!
Finally, optionally adding borates to your water at 30-50 ppm concentration will help with pH stability with a SWG, particularly when the TA is run in the 60-80 ppm range and pH is kept between 7.6-7.8. There are several borate products on the market–Supreme Plus, Optimizer, Maximizer, Endure, and 20 Mule Team Borax. You can buy 20 Mule Team Borax at the grocery store in the laundry aisle. If you don’t know how to use borates, read this article on adding borates or just start a thread on our forums asking for info on how to do it.
To summarize:
FC: 5-7 ppm
pH: 7.2-7.8
TA: 60-80
CH:
- 50-300 for vinyl (do not add CH!)
- 225-350 for fiberglass
- 350-450 for plaster
CYA 70-80
Borates 30-50 ppm (optional)
