How do I Winterize a Saltwater Pool?

Balance the water, clean the salt cell, and add winterizing chemicals before covering the pool securely.

Why Winterizing Matters

Saltwater pools have unique components that need special care. Unlike traditional chlorine pools, they rely on a salt cell and control system. Cold temperatures and stagnant water can do serious damage if you skip the winterizing process.

Winterizing helps prevent:

• Frozen and cracked plumbing

• Damage to the salt cell and control panel

• Algae and stains from unbalanced water

• Corrosion of metal parts

• Costly equipment repairs in the spring

• Delayed pool opening due to unexpected damage

Step-by-Step: How to Winterize a Saltwater Pool

Step 1: Deep Clean the Pool

Start with a spotless pool so you’re not trapping organic material that could cause staining or algae.

• Skim the surface for floating debris

• Brush the walls, steps, and tile line to loosen dirt and algae spores

• Vacuum the entire pool, especially corners and crevices

• Clean out the skimmer and pump baskets thoroughly

This ensures you're not sealing in contaminants that will fester over winter.

Step 2: Balance the Water Chemistry

Properly balanced water is less likely to damage surfaces or equipment during the off-season. Use a test kit or bring a sample to a pool store.

Target ranges:

• Chlorine: 1 to 3 ppm

• pH: 7.4 to 7.6

• Alkalinity: 80 to 120 ppm

• Calcium hardness: 200 to 400 ppm

• Cyanuric acid: 30 to 50 ppm

• Salt: Follow your system’s specific recommendation, typically 2,700 to 3,400 ppm

If your water levels are off, adjust them in small doses and allow 12 to 24 hours of circulation between changes.

Step 3: Add a Shock and Algaecide

Before closing the pool, eliminate any lingering contaminants.

• Shock the pool with chlorine or non-chlorine oxidizer 1 to 2 days prior to closing

• Use a quality winter algaecide that prevents algae blooms

• Allow the system to run for at least 12 hours to circulate chemicals

This extra step improves water clarity and reduces the risk of green water in spring.

Step 4: Turn Off and Disconnect the Salt Chlorine Generator

Salt cells cannot handle ice or freezing water. Disconnecting them helps protect your equipment.

• Turn off the salt chlorination system completely

• Detach the salt cell from the plumbing line

• Rinse gently to remove scale or residue

• Store indoors in a clean, dry area

If your salt system has a flow sensor or inline controller, store those components safely as well.

Step 5: Lower the Water Level

Reducing the water level below the skimmer prevents ice from damaging those components.

• Use a sump pump or pool pump on waste mode to drain the water

• Do not empty the pool completely

• Leave 4 to 6 inches below the skimmer opening

Keep an eye on the liner and structure if you have a vinyl or fiberglass pool. Too much water loss can cause structural stress.

Step 6: Drain and Protect the Equipment

Freezing water in pipes or equipment will cause major issues.

• Remove drain plugs from all pumps, filters, and heaters

• Disconnect unions and hoses to fully empty components

• Use a shop vac or air compressor to blow water out of all lines

• Add pool-grade antifreeze if your system requires it

Place all drain plugs and small parts in a sealed bag and store them in the pump basket or a labeled container.

Step 7: Plug the Lines and Add Winterizing Devices

Block water from re-entering the system and install devices that help prevent damage.

• Insert freeze plugs or rubber expansion plugs in all return lines

• Use a skimmer guard or gizzmo to absorb ice expansion

• In above-ground pools, place an air pillow in the center to relieve ice pressure

Make sure all plugs are tight and properly seated to avoid leaks.

Step 8: Cover the Pool

Your cover acts as a barrier between your clean pool and months of debris, light, and precipitation.

• Use a tight-fitting, solid safety cover or a heavy-duty winter tarp

• Secure it with water bags, straps, or anchors depending on pool type

• Periodically clear leaves, water, and snow buildup

Avoid mesh covers unless you plan to check water balance regularly throughout the winter.

Additional Tips for Saltwater Pools

• Clean the salt cell with a scale remover if calcium buildup is visible

• Turn off breakers to the salt system and pump to prevent accidental starts

• Label all pool parts for easy reassembly in the spring

• Store unused chemicals in a cool, dry place away from moisture

• Check the pool water once a month if winter thaws allow for access

What to Avoid When Winterizing a Salt Pool

• Skipping the water balance step or guessing on levels

• Leaving the salt cell or flow switch attached

• Using RV or automotive antifreeze (only use pool-safe antifreeze)

• Forgetting to blow out return lines and main drain if applicable

• Covering a pool with algae or scale still present

Taking a methodical approach to winterizing your saltwater pool not only protects your investment, it also ensures a faster and easier opening when the warm season returns. Plan ahead, check everything twice, and your pool will thank you when spring rolls around.