If you have a saltwater pool, choosing the right pool salt might seem simple, but the type of salt you use can make a real difference to water quality, equipment performance, and ongoing maintenance.

Here’s what to look for when choosing pool salt, and how to make the best choice for your pool.

1. Always Use Salt Made for Pools

Not all salt is the same. Pool salt is specially refined for use in swimming pools.

Pool-grade salt is:

• High purity, usually 99% or higher sodium chloride

• Free from anti-caking agents and additives

• Safe for salt chlorinators and pool surfaces

Household or rock salt can contain impurities that may:

• Cloud the water

• Damage chlorinators

• Cause staining or scale buildup

2. Fine vs Coarse Pool Salt – What’s the Difference?

Both fine and coarse pool salt can be used in saltwater pools, but they behave differently once added to the water.

Fine pool salt:

• Dissolves quickly

• Spreads evenly through the pool

• Helps reach correct salinity faster

• Is gentler on pool surfaces

Coarse pool salt:

• Takes longer to dissolve

• May sit on the pool floor if not brushed

• Is better suited to large pools with strong circulation

For most pools, fine pool salt is the easier and safer option.

3. Consider Your Pool Size

Smaller pools benefit from salt that dissolves quickly and evenly.

Fine pool salt is ideal because:

• It reduces the risk of salt settling on the pool floor

• Salinity levels stabilise faster

• It makes dosing easier and more accurate

4. Protect Your Salt Chlorinator

Salt chlorinators rely on stable salinity levels to operate efficiently.

Using high-quality, fine pool salt helps:

• Prevent low-salt warnings

• Produce more consistent chlorine

• Reduce scale buildup on the salt cell

• Reduce the need for salt cell cleaner

• Extend the life of the chlorinator cell

Coarse salt dissolves more slowly and can contribute to scale forming on the cell plates, which may mean more frequent cleaning over time.

5. Apply Pool Salt Correctly

No matter which salt you choose:

• Add salt with the pump running

• Spread it evenly around the pool

• Brush any undissolved salt from the pool floor

• Wait 24 hours before retesting salinity

Fine salt reduces the time and effort required during this process.

Final Tip

Every pool is different. The best pool salt choice can depend on pool size, surface type, chlorinator brand, and water conditions.

If you’re unsure which pool salt to use or how much to add, the team at The Spa Shop can provide practical advice and help you choose the right option for your pool. Bring a water sample in-store and we’ll test it for you with a free water test, so you can be confident your pool is perfectly balanced.