Saltwater Pool Start Up Kit

A start up kit is a bundle of opening chemicals, usually a clarifier, an algaecide, a stain and scale preventative and a shock, dosed by pool size. There is no saltwater version, and you do not need one. What a salt pool needs in spring is not a different chemical, it is a different order of operations, and getting that order wrong is how people scale a brand new cell in the first week of the season. The short version: cell in, controller off, filter running, water balanced, then shock, then test salt, then add salt, and the salt system goes on last.

The kit is fine. The sequence is the thing.

Nothing in a start up kit is bad for a salt pool. A clarifier clears the haze that a winter under a cover leaves behind, and the algaecide and preventative do the same job they do in any pool. If pre measured doses save you a trip and an hour with a label, buy it.

But the kit tells you what to add. It does not tell you when, and in a salt pool the when is everything. In The Swim’s saltwater opening guide sets the sequence out and is blunt about the part people get wrong: Do NOT turn on the salt cell just yet!

The order, and why each step sits where it does

Reinstall the cell first, with pool lubricant on the union o rings, and the controller plugged in but left OFF. Powered but not generating is the state you want, because the panel can then show you a salt reading without the plates doing any work.

Then prime the pump, backwash and filter. Then balance. Only after that do you shock, and the reason is the sentence in that guide worth reading twice: wait to shock the pool until you have properly balanced the water. If you shock first, your chlorine may not work efficiently, and you will put your pool at risk for stains and scaling issues. Chlorine added to water that is off on pH is chlorine you have paid for and will not fully get. Our salt water pool shock page covers the dose once you are ready for it.

Salt comes after the shock, not before it, and the system comes on after the salt. The point of that last step is simple. The cell makes chlorine by pushing current through water, and everything that comes out of the plates is decided by the water already sitting in the pipe. Start it into water with high pH and high calcium and the plates begin building deposit immediately, which is the mechanism behind salt cell calcium buildup. A cell that scales in April will read low salt in June and get replaced in August by an owner who thinks the cell failed.

The opening ranges

In The Swim’s opening targets for a saltwater pool:

All four are from the saltwater opening guide. Note that its pH window is tighter than the 7.2 to 7.8 range Hayward publishes for ongoing operation. That is deliberate on an opening. You are about to hand the pool to a device that pushes pH up on its own, because hydrogen gas off gassing from the cell aerates the water, drives off carbon dioxide and raises pH. Starting at the top of the range means you are chasing acid by Memorial Day. Start low in the range instead.

Cyanuric acid at opening is worth its own test, because an uncovered pool loses it slowly over a season and a covered one mostly does not. Sort it before the cell runs, using cyanuric acid for pool if you need to raise or lower it.

The spring salt top up, with the arithmetic

Most saltwater pools need a booster dose of salt in spring, usually 10 to 20%. Rain, splash out, backwashing and the water you pumped off the cover all dilute it over a winter.

Do not take that dose from the panel. In spring the water is cold, and a cell has no salt sensor. It reads conductivity and infers salinity, and cold water conducts less, so the display reads low while the salt has not moved. Test the water itself, then dose.

The arithmetic is worth doing by hand once so you can check any calculator against it. Pounds of salt equals gallons times the ppm you need, divided by 120,000, because 1 lb of salt per 1,000 gallons raises salinity by 120 ppm.

Take a 20,000 gallon pool that tests at 2,600 ppm against a 3,200 ppm target. You need 600 ppm.

• 20,000 x 600 = 12,000,000
• 12,000,000 / 120,000 = 100 lb

That is two and a half 40 lb bags. Framed as a percentage of a 3,200 ppm target, a 10 to 20% booster is 320 to 640 ppm, which in the same pool is 53 to 107 lb. Our pool salt calculator runs the same formula, and if you are unsure of your gallons, the pool volume calculator is the input everything else depends on. An error in volume is an error in every dose you will make all year.

Add salt with the pump running and give it time to dissolve and circulate before you believe any reading, then turn the system on.

One exception: a brand new plaster pool

If the pool has just been plastered, do not start with salt at all. Hayward’s chemistry guide says to wait 10 to 14 days before adding salt to new plaster. Fresh plaster is still curing and still moving the water chemistry around, and salt added into that is salt you cannot take back out without draining.

After opening week

Once the system is on, the job changes from a sequence to a habit. Weekly testing, pH control and watching what the panel is actually telling you are covered on salt water pool maintenance, and the products worth keeping on the shelf are on salt water pool chemicals. The reverse of everything here, including why you should not top salt up in fall, is on salt water pool closing kit. Everything else we have written about generators sits on the salt cell hub.

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