Salt vs chlorine vs mineral in Pakenham - the 10-year running cost.
Three systems, same 8×4m pool, same Cardinia Shire water, same swim season. The cell-replacement cycle, the chemistry bill, the equipment-shed footprint and the skin-friendliness reality - with the numbers our techs see on real Pakenham pools.
The 10-year cost table.
We service roughly 180 Pakenham, Officer, Beaconsfield, Cardinia Lakes and Heritage Springs pools across all three sanitisation systems. The numbers below are averages from real visit records and supplier invoices - not brochure figures.
Salt chlorination - the Pakenham default.
Roughly 78% of new pools we’ve commissioned in Cardinia Shire since 2018 went in as salt. Capex is the chlorinator power supply ($900-$1,400) and the in-line cell ($1,100-$1,500 installed). After that, you’re running about 4-5kg of pool salt per 1,000L of make-up water (rain dilutes salinity), plus the usual acid and stabiliser. Salt cell life is the big variable - we plan for one replacement at year 4 and a second around year 9. Free-chlorine residual should sit 1-3ppm like any other chlorine pool; owners forget that salt water is chlorinated water, just made on-site.
Ten-year all-in: $4,800-$5,400 on a standard family pool. Cheapest of the three.
Liquid / granular chlorine dosing.
Same pump and filter setup, no cell, no power supply. Sanitiser comes in either as liquid sodium hypochlorite from the van or as granular cal-hypo dosed by hand or auto-feeder. No mid-life cell to replace, but you’re buying chemistry every visit - we typically budget $50-$60 a month on chlorine alone for an 8×4. Stabiliser (cyanuric acid, AS/NZS 1838 recommends 30-50ppm in outdoor pools) matters more here because there’s no cell making fresh chlorine throughout the day.
Ten-year all-in: $6,200-$7,200. The “cheaper to install” option is the most expensive to run.
Mineral (magnesium / potassium) systems.
Mineral pools blend magnesium chloride and potassium chloride with a small amount of sodium chloride, then run a chlorinator cell across that brine. Capex includes the same chlorinator gear as salt, plus a mineral reservoir or initial mineral fill that costs $1,400-$2,200 on a fresh pool. Maintenance mineral salt is roughly three times the price of pool salt by weight. The reverse-polarity cell wears about the same as a salt cell - 3-5 years.
Ten-year all-in: $7,800-$8,600. The comfort upgrade is real but modest, and you pay for it every year.
What “skin-friendly” actually means.
The marketing on mineral pools leans hard on skin comfort. The truth from a tech’s bench: free chlorine target is 1-3ppm on every one of these systems. Salt pools are not “chlorine-free” - they make chlorine on-site by electrolysing dissolved salt. Mineral pools still need a residual chlorine level too. What actually drives skin and eye comfort in a Pakenham pool is:
- pH inside 7.2-7.6: high pH (above 7.8) burns eyes and dries skin far more than chlorine concentration does.
- Combined chlorine below 0.5ppm: that “chlorine smell” isn’t free chlorine, it’s combined chloramines - the sign you need a 10x shock dose, not less chlorine.
- Stabiliser inside AS/NZS 1838 range: 30-50ppm CYA. Over 80ppm and chlorine effectiveness collapses; you end up dosing more for the same kill.
- Total dissolved solids under 1,500ppm (above the salt baseline): high TDS reduces water clarity and the “soft” feel that mineral pools are sold on.
A well-tuned salt pool with pH in band and CYA inside the AS/NZS 1838 range will feel better than a neglected mineral pool every weekend of the year.
Equipment shed footprint - what fits where.
Cardinia Lakes and Heritage Springs new-build pads were designed with chlorinator gear in mind - any of the three systems fit comfortably. Older retrofit pools around central Pakenham can be tight; we’ve done several where a mineral reservoir wouldn’t fit and the owner reverted to straight salt. If you’re inside a 1.2m x 0.6m equipment slab, expect: salt just fits, chlorine dosing fits with a wall-mount tank, mineral usually doesn’t without extending the slab.
We’ll come out, measure the pad and tell you straight which systems are practical - no charge, just a 15-minute look. Call (03) 9003 0108 or email quotes@pakenhampoolcare.com.au.
Common questions.
Can I convert from chlorine to salt without re-piping?
Almost always yes - we cut in the cell housing on the return line and wire the power supply into the existing equipment circuit. Half-day job, parts $1,800-$2,400 plus a salt load (about 7-8 bags at 20kg for a standard family pool). Existing filter, pump and heater stay.
If I go mineral, do I still need to dose chlorine manually?
Only on heavy bather load or after rain dilution. The chlorinator behind the mineral system handles day-to-day chlorine production. We still run a 10x shock chlorine dose (10ppm free chlorine for breakpoint) twice a season on mineral pools because chloramines build the same as anywhere else.
Does a pool cover make a salt pool cheaper to run?
Yes - significantly. A bubble cover cuts evaporation by 70%+ which keeps salinity stable (less make-up water dilution), drops chlorine demand by 30-50%, and extends cell life by reducing run-hours. Pool cover ROI on a heated Pakenham pool is 18-24 months in chemistry, heating and water savings combined.
Are mineral pools safe for someone with magnesium sensitivity?
Almost no-one is sensitive to magnesium at typical pool concentrations (~1,000-3,000ppm Mg2+), but if a family member has documented sensitivity, default back to salt - the magnesium load in a salt pool is negligible.
Not sure which system suits your Pakenham pool?
Free 15-minute on-site look. We measure the equipment pad, test current water, and tell you the 10-year cost on each option for your pool. No upsell, no pressure.