When you add salt to your salt water pool, you’re better adding too little than too much.
It’s much easier to quickly raise the level of salt in your pool than it is to quickly lower it. Excessively low salt makes your chlorinator work harder whereas excessively high salt can corrode metal and damage pool equipment.
Over time the salt level will go down and you will need to add salt to your pool possibly several times per year. It is important to keep the salt level within range at all times.
Here are the most common mistakes salt water pool owners make regarding the salt they add to their pool.
The salt level is too low in your pool
Follow the instructions of your salt chlorination system manufacturer and keep the salt level within range. This is typically in the range of 2700 ppm – 3400 ppm where ppm = parts per million.
When salt gets too low, it become more difficult for your chlorinator to produce enough chlorine which can lead to the salt cell dying prematurely and having to be replaced at your expense.
It also makes it more likely that your pool water will not be crystal clear and that green algae may develop.
If you keep the salt level close to the higher end around 3200 ppm or so, you’ll ensure you have enough salt in the water for the chlorinator to work properly and produce chlorine even when salt is inevitably lost over time.
Which it will be.
While salt doesn’t evaporate, it is lost through normal pool use, leaks, splashing and other reasons. So if you keep the salt level closer to the high end of the allowed range, you’ll be less likely to have a problem with low salt during the season that can lead to cloudy water.
Salt chlorinators are also programmed to shut off once salt levels get too low to protect the system which means your pool won’t produce chlorine and the water will start to get dirty.
Typically if the salt level gets down to around 2300 ppm, chlorine production will automatically shut off until the salt level is raised. Your system may display a low salt warning error message.
The salt level is too high in your pool
Typically if the salt level goes above 3400 ppm to the 3500 ppm – 4000 ppm range, chlorine production will automatically shut off depending on the system you have. Your chlorinator system may display a high salt warning error message.
When salt levels get excessively high, water can get corrosive and can damage metal in your pool such as a pool ladder or even the plates inside the salt cell. If your salt cell comes with a self-cleaning option such as a reverse polarity feature, it can help to keep it clean but a very high salt level can damage pool equipment over time.
As an aside, you’ll actually tend to start to taste saltiness in the pool water in the 3500 ppm – 4000 ppm range.
The only way you can quickly lower the salt level in your pool water is to drain an amount of water out and then refill it with fresh water. The problem is that you’ll also drain chemicals from the pool that may also need to be replaced.
Plus, if you drain too much water, you’ll have to add it back at your expense and then might find you accidentally lowered the salt level too much, and have to add more salt too.
If your salt level is slightly high but still close to being in range, you might simply do nothing as over time, the salt level will come down through regular pool usage during the swimming season.
You’re adding the wrong salt to your pool
Use the type of salt recommended by your chlorinator manufacturer or pool company. While you can generally use white salt pellets made for a water softener, you can also of course use crystalized pool salt that is made specifically for pool use.
White salt pellets can be dumped directly in the deep end of the pool and they will dissolve over a day or so. Since they are designed for water softener use, they don’t dissolve right away but they will break up over about 24 hours.
Pool salt on the other hand is in crystal form already and will dissolve much quicker. When you dump it into the pool it’ll disappear pretty much right away and can enter the pump and chlorinator faster to get converted to chlorine.
Having said that, I’ve always used white salt pellets for our salt water pool and our Hayward chlorinator works just fine.
You’ll pay more for pool salt than for white water softener pellets.
Do not use road salt, table salt or any salt that is multi-colored. Stay away from water softener salt that has other additives meant for a water softener such as calcium reducer as you’re just paying for something your pool doesn’t need and it could negatively affect the pool chemistry.
Final thoughts on the salt level in your pool
- Be especially careful about keeping your salt level in range if you have a concrete pool. While a vinyl pool liner, fiberglass pool and your salt cell can generally withstand a higher level of salt, a concrete-lined pool can be damaged over time with excessively high salt.
- Excessively high salt levels in any pool can corrode metal and other parts of your pool equipment.
- Salt does not evaporate, wear out or suddenly disappear. The salt level in a pool decreases over time due to splashing, backwashing, leaks and other ways that water gets lost in a pool.
Summary
Salt levels in your pool will fluctuate and over time will go down. This is why you need to add salt to your pool each season and possibly several times depending on how much water you lose.
If you’re losing salt excessively, there are typically several reasons for this occurring. Check out my article on why you’re losing salt in your pool as it might not be the reason(s) that you think it is.