Converting a chlorine pool to salt water is a much smaller job than most people expect. You are not rebuilding the pool, replumbing the pad, or draining anything. You are adding one piece of equipment to the return line, tipping some bags of salt into the water, and letting the pump do the rest. A competent DIYer can have it running in an afternoon, and the whole thing usually lands somewhere between 800 and 2,500 dollars. What decides whether the conversion goes smoothly is not the installation, it is the handful of checks you do beforehand, and that is where most guides go quiet. Here is the whole process, including the parts worth pausing over.
The single most useful thing to understand before you start is what a conversion actually is. A salt water pool is not a different kind of pool, it is a chlorine pool that makes its own chlorine from salt dissolved in the water. Nothing about the shell, the liner, the plumbing or the filter changes. You are swapping a delivery method, not a system. If that is news, do salt water pools have chlorine covers the chemistry properly and will save you a lot of confusion later.
Because of that, converting is mostly an exercise in three things: choosing the right size generator, getting your water numbers right before you switch it on, and adding the correct amount of salt. The pool salt calculator handles the third one in about ten seconds, which leaves you free to concentrate on the first two.
Enter your pool volume, your current salt reading and your target ppm into the Waldev pool salt calculator and it will tell you how many bags the initial fill needs, so you can budget the whole conversion accurately.
What this guide covers
The short version
Balance the water, buy a generator rated for at least one and a half times your pool volume, plumb the cell into the return line after the filter and heater, wire it to a dedicated circuit, add salt to reach about 3,000 ppm, circulate for a day, then turn it on at half output and adjust from there. That is the entire conversion.
The pool stays full the whole time. You swim in it that same week. The main thing you are buying is the end of weekly chlorine handling, and the main thing you are taking on is more attention to pH.
The order matters more than anything else here. Balance first, install second, salt third, switch on last. Doing it in that sequence prevents nearly every problem people report in the first month after converting.
What a conversion actually involves
Strip away the marketing and there are only two physical changes to your pool.
The first is a short section of pipe on the equipment pad. The salt cell is a clear or opaque cylinder with a stack of coated titanium plates inside, and it gets plumbed into the return line as the last piece of equipment before the water goes back to the pool. Water passes through it, a low current passes between the plates, and chlorine is produced continuously while the pump runs.
The second is the salt itself, dissolved in the water at around 3,000 parts per million. That is roughly a tenth of seawater and about a third the saltiness of a tear, which is why most people can barely taste it. The salt is the raw material the cell works with, and because chlorine reverts to salt after it has sanitised, you are not really consuming it. You top up for splashout, backwashing and rain overflow, not for chlorine production.
Everything else stays. Same pump, same filter, same skimmers, same returns, same water. If you ever want to reverse the decision, you unplug the generator and go back to tablets, which is covered in converting a salt water pool back to chlorine.
Check these five things before you spend a dollar
This is the section that separates a smooth conversion from an expensive lesson. None of these take long, and any one of them can change your decision.
Your heater. Look up the model and find out whether the heat exchanger headers are rated for salt water. Anything made in the last fifteen years or so usually is, but older copper headers can corrode noticeably faster in salted water. Replacing a heater costs more than the entire conversion, so make this the first call you make.
Your coping and decking. Poured concrete and most manufactured pavers are fine. Porous natural stone, particularly some limestones and sandstones, can spall and flake where salted water splashes and evaporates. Sealing the stone before conversion is cheap; repairing it afterwards is not.
Metal in and around the pool. Handrails, ladders, light rings, diving board hardware, and any exposed rebar or wall fastenings. Stainless holds up well but will pit over years, so plan on a sacrificial zinc anode and be realistic about older galvanised parts.
Electrical capacity. A generator needs a dedicated circuit, correctly bonded and protected. If your equipment pad has no spare capacity or no room in the panel, add the cost of an electrician to your budget before you decide.
Your current water chemistry. Test stabiliser, calcium hardness and metals. Stabiliser well above 100 ppm, calcium hardness above 500, or copper and iron in the water will all cause trouble in a salt pool, and the fix is usually a partial drain and refill. Better to know now.
Ask your builder or warranty provider first if the pool is new. A small number of pool finishes and coping installations carry warranty language about salt systems. It is a five-minute email that occasionally saves an argument years later.
The equipment you actually need
The parts list is shorter than most people expect, and much of it comes in one box.
| Item | What it does | Typical cost |
|---|---|---|
| Salt cell | The coated titanium plates that make the chlorine | Included with the system; 300–700 to replace later |
| Control box / power supply | Converts mains power to low-voltage DC, sets output, reads salt | Included with the system |
| Complete generator system | Cell plus control box, sized to your pool | 500–1,800 |
| Flow switch | Stops chlorine production when there is no water flow | Usually included or built into the cell |
| Unions and fittings | Plumbing the cell into the return line | 20–60 |
| Pool salt | The raw material; 99% pure sodium chloride | 8–15 per 40 lb bag |
| Sacrificial zinc anode | Corrodes instead of your metal fittings | 30–80 |
| Salt test strips or meter | So you are not relying on the panel reading alone | 10–60 |
| Stabiliser | Salt pools want a higher CYA than tablet pools | 20–40 |
The zinc anode deserves a word because it is the most commonly skipped item and the cheapest insurance on the list. It is a lump of zinc that sits in the water flow or in the skimmer and corrodes preferentially, protecting the more valuable metal in the system. Thirty to eighty dollars, replaced every couple of years, and it noticeably slows down the pitting people complain about on rails and light rings.
Sizing the generator, and why bigger is better
This is the decision with the longest consequences, because getting it wrong quietly costs you a cell every few years.
Manufacturers rate systems by the maximum pool volume they can sanitise. The temptation is to buy the one that matches your pool. The problem is that a matched system has to run near full output all season to keep up, and running at high output means more current through the plates, more scaling, and a cell that wears out faster. It also leaves you no headroom for a heatwave or a weekend with fifteen kids in the pool.
Rule of thumb: buy a generator rated for at least 1.5 × your actual pool volume
Hot climate, heavy use, or little shade: go to 2 ×
A 20,000 gallon pool → buy a system rated for 30,000–40,000 gallons
| Your pool volume | Minimum system rating | Better choice in hot climates |
|---|---|---|
| 10,000 gallons | 15,000 gallons | 20,000 gallons |
| 15,000 gallons | 22,000 gallons | 30,000 gallons |
| 20,000 gallons | 30,000 gallons | 40,000 gallons |
| 25,000 gallons | 40,000 gallons | 40,000–60,000 gallons |
| 30,000+ gallons | 40,000–60,000 gallons | 60,000 gallons or two cells |
The price difference between a 20,000 and a 40,000 gallon system is usually two or three hundred dollars. The difference in cell life can be years. It is one of the few places in pool ownership where spending more upfront is straightforwardly the cheaper decision. If you do not know your pool volume accurately, measure it properly rather than guessing, because every calculation downstream depends on it.
What converting actually costs
Here is a realistic budget rather than a best case. Prices vary by region and brand, but these bands cover most residential conversions.
| Line item | Above ground pool | Inground pool |
|---|---|---|
| Generator and cell | $250–600 | $500–1,800 |
| Initial salt load | $40–80 | $50–150 |
| Plumbing fittings | $15–40 | $20–60 |
| Zinc anode | $30–60 | $40–80 |
| Electrical work | Often none, plug-in units | $150–500 |
| Professional install | $0–200 | $300–800 |
| Balancing chemicals | $30–80 | $40–120 |
| Realistic total | $400–900 | $800–2,500 |
Against that you save roughly 300 to 700 dollars a year in chlorine, depending on pool size and climate, and you spend perhaps 30 to 70 a year on salt plus a little more electricity. Set against a cell replacement every four to six years at 300 to 700 dollars, the honest payback is usually two to four seasons. The full running-cost picture, including what a salt pool costs year on year, is in how much a salt water pool costs.
Which is to say: if your only motivation is money, the case is thin. Most people convert because they are tired of handling chlorine and because the water is more pleasant, and the savings are a bonus rather than the argument.
Balance the water before the generator goes anywhere near it
A salt cell is not a water treatment system, it is a chlorine factory. It cannot fix bad water, and starting one in a pool that is out of balance simply bakes the problem in. Get these numbers right first.
| Reading | Target before conversion | Why it matters |
|---|---|---|
| Free chlorine | 1–3 ppm, water clear | Start from a clean pool, not a recovering one |
| pH | 7.2–7.4 | Salt pools drift up, so start at the bottom of range |
| Total alkalinity | 70–90 ppm | Lower than a tablet pool; makes pH easier to hold |
| Calcium hardness | 200–350 ppm | Above 400 and the cell will scale constantly |
| Stabiliser (CYA) | 60–80 ppm | Higher than a tablet pool; protects generated chlorine |
| Metals (copper, iron) | Zero, ideally | Salt water can mobilise metals and cause staining |
| Phosphates | Under 200 ppb | High phosphates feed algae the cell cannot outpace |
Two of these catch people out. Stabiliser needs to be higher than you are used to, because the chlorine a cell produces is unprotected and sunlight destroys it quickly. And calcium hardness matters far more than it did before, because the cell is exactly where excess calcium likes to deposit. If your fill water is hard, read how to clean a pool salt cell now rather than in three months, because you will be doing it.
The conversion, step by step
Take a full test to a pool store or use a good drop kit. Adjust alkalinity first, then pH, then calcium and stabiliser. Give the pool a day or two to settle between adjustments rather than dosing everything at once.
Brush the walls, vacuum, empty the baskets, and backwash or clean the filter. A conversion is a natural moment to start with genuinely clean equipment, and a dirty filter will slow the first week of chlorine build-up.
Shut the pump down and release pressure at the filter’s air relief before you cut into anything. Do not rely on a timer or automation schedule to stay off.
The cell goes last, after the filter and after the heater, so it only ever sees filtered water and never sees the hottest water. Cut in the unions, dry-fit everything first to check alignment, then glue. Leave the cell horizontal or per the manufacturer’s orientation marking.
Mount the box within cable reach of the cell, out of direct spray, at the manufacturer’s minimum distance from the water. The circuit must be dedicated, bonded and protected to code. If that sentence is not completely familiar to you, this is the part to hire out.
With the generator still switched off, run the pump for a few minutes and inspect both unions. Purge the air from the filter until water flows steadily from the relief valve.
Test the existing salt level first; most pools already carry a few hundred ppm. Run the numbers through the pool salt calculator, then broadcast the salt across the deep end with the pump running. Never pour salt into the skimmer.
Brush the salt off the floor to help it dissolve and run the pump continuously for a full day. Salt sitting undissolved in a pile on the plaster can etch it, and a cell reading taken before the salt has distributed will be wrong.
Test with strips or a meter rather than trusting the panel on day one. Panel readings on a brand new install often need a full circulation cycle to settle.
Start in the middle of the output range rather than at full. Give it 24 hours, test free chlorine, and adjust up or down. Most pools settle somewhere between 40 and 70 percent once the pool is stable.
How much salt the conversion needs
The arithmetic is simple enough to sanity-check by hand, even though the calculator is faster.
Pounds of salt = pool gallons × (target ppm − current ppm) ÷ 120,000
Example: 20,000 gallons, currently 400 ppm, target 3,200 ppm
20,000 × 2,800 ÷ 120,000 = 467 lb, which is twelve 40 lb bags
| Pool volume | Salt from 0 ppm to 3,000 ppm | 40 lb bags |
|---|---|---|
| 5,000 gallons | 125 lb | 3 bags |
| 10,000 gallons | 250 lb | 6 bags |
| 15,000 gallons | 375 lb | 9 bags |
| 20,000 gallons | 500 lb | 12 bags |
| 25,000 gallons | 625 lb | 15 bags |
| 30,000 gallons | 750 lb | 18 bags |
Two practical notes. First, always subtract the salt already in your water, which is often 300 to 800 ppm in a pool that has been sanitised with liquid chlorine for years, because liquid chlorine leaves salt behind. Skipping that step is the single most common cause of overshooting. Second, aim slightly below your target and top up, because adding salt is easy and lowering a salt level means draining and refilling water.
On technique, the method matters as much as the quantity. Broadcast it across the deep end in a wide arc, keep the pump running, and brush it around. There is a full walkthrough in how to add salt to a pool the right way, and if you want the quantity question in more depth, how much salt to add to a pool covers the variations.
Do not swim for the first few hours after adding a large salt load. Undissolved salt on the floor is abrasive and unpleasant underfoot, and the water needs circulation time to even out. Most manufacturers suggest waiting until the salt has fully dissolved, which is usually a matter of hours rather than days.
What the first week looks like
Expect a settling-in period rather than instant perfection. Here is the normal sequence.
| When | What to do | What is normal |
|---|---|---|
| Day 1 | Salt added, pump running continuously, generator off | Slight cloudiness as salt dissolves; brush the floor |
| Day 2 | Verify salt level, switch generator on at 50% | Panel reading may differ from your test kit at first |
| Day 3–4 | Test free chlorine daily | Chlorine climbing slowly; adjust output up if under 1 ppm |
| Day 5–7 | Test pH, expect it to rise | Add acid as needed; this is the biggest ongoing change |
| Week 2 | Settle on an output percentage | Most pools land between 40 and 70 percent |
| Week 3–4 | Recheck stabiliser and salt | Fine-tuning rather than fixing |
The pH climb is the thing new salt pool owners are least prepared for. Electrolysis pushes pH upward as a side effect, so a pool that used to sit still at 7.5 may now creep toward 7.8 or 8.0 within a week. It is completely normal and entirely manageable, but it means testing twice a week rather than once a fortnight. Lowering pH in a salt pool covers the routine.
Once the pool is stable, the weekly rhythm is short. Maintaining a salt water pool sets out what to test and when, and the right salt level for your pool gives you the number to hold.
Converting different types of pool
Above ground pools
The cheapest and simplest conversion, because above ground systems are smaller, often plug into a standard outlet, and need no trenching or panel work. The one genuine consideration is the wall. Steel-walled pools can corrode where the liner has been nicked or where salted water sits on top rails after splashing, so resin and hybrid pools are better candidates. Keep salt at the low end of the recommended range and give the top rails an occasional rinse. There is more on this in can an above ground pool be salt water.
Vinyl liner inground pools
Straightforward. The liner does not care about salt at all. The parts to watch are the metal wall panels behind the liner if there is any damage, and the stair or step structures if they are steel. Most vinyl pools convert with no drama.
Fiberglass pools
Arguably the best match for salt water. The gelcoat surface is completely unaffected, there is no plaster to worry about, and fiberglass pools tend to have fewer metal components in contact with the water. If you have a fiberglass shell, the conversion decision comes down to equipment and coping rather than the pool itself.
Concrete, plaster and pebble pools
Fine in themselves, but this is where water balance matters most. Plaster is vulnerable to aggressive water, so calcium hardness and pH need genuine attention rather than occasional glances. The coping and any natural stone surround are the components most worth inspecting and sealing before you convert.
Corrosion, without the scaremongering or the denial
You will find forum threads claiming salt destroys everything and manufacturers claiming there is no issue at all. Reality sits in between, and the deciding factor is usually whether the pool is run at the correct salt level.
At 3,000 ppm, salted pool water is mildly more conductive and mildly more corrosive than plain chlorinated water. That is enough to matter for a few specific things over a period of years: stainless handrails and ladders, light rings, older heater headers, some natural stone, and any exposed steel. It is not enough to threaten liners, fiberglass, plaster, PVC plumbing or modern pumps and filters.
The practical protection package is short: fit a sacrificial zinc anode, seal porous stone, rinse splash areas occasionally, and keep salt inside the manufacturer’s range rather than assuming more is better. Do those four things and corrosion becomes a maintenance detail rather than a problem.
Doing it yourself versus hiring someone
The plumbing is genuinely DIY-friendly for anyone who has glued PVC before. Two unions, a section of pipe, dry fit, glue, done. The electrical side is not, unless you are qualified. Pool equipment circuits need correct bonding and protection, and this is water and mains electricity in the same yard.
The middle path most people take is sensible: do the plumbing and the salt yourself, hire an electrician for the circuit. That typically costs 150 to 500 dollars and takes an hour or two, and it is the part of the job you genuinely do not want to guess at.
Comfortable to DIY
Cutting in the cell, gluing unions, mounting the control box on a wall, calculating and adding salt, brushing, testing, setting the output percentage, fitting a zinc anode.
Worth paying for
Running a new circuit, panel work, bonding, anything involving old or brittle plumbing that may crack, and any situation where the equipment pad layout means the cell will not fit without rework.
Mistakes that make a conversion go badly
Not testing existing salt before dosing. Pools sanitised with liquid chlorine often already sit at 500 to 1,000 ppm. Adding a full load on top of that overshoots, and the only way back down is draining water.
Buying a system matched to the pool size. Undersized generators run flat out all summer, scale faster and die younger. One and a half times volume is the minimum sensible rating.
Pouring salt into the skimmer. A concentrated slug of salt through the pump and heater is exactly what you do not want. Broadcast it into the pool instead.
Switching the generator on before the salt dissolves. The cell will read wrong, you will chase a number that is not real, and you may end up adding more salt on top of salt that has not distributed yet.
Using the wrong salt. Water softener pellets, rock salt with anti-caking agents, or iodised table salt all bring problems. Use pool-grade 99% pure sodium chloride, as explained in pool salt versus water softener salt.
Forgetting stabiliser. Converting a pool that ran on trichlor tablets sometimes means stabiliser is already too high. Converting one that ran on liquid chlorine often means it is far too low. Test rather than assume.
Ignoring pH for the first fortnight. The upward drift starts immediately. Pools that get away from you in the first two weeks are usually the ones people describe as “the salt system never worked properly”.
When converting is not the right call
Being honest about this saves people money. There are situations where staying with tablets or liquid chlorine is simply the better decision.
If your pool is only open for a short season, the payback maths gets very stretched, and a generator sitting unused for eight months a year is not doing much for you. If your fill water is extremely hard, above 500 ppm calcium, you will fight scale continuously unless you address the water source first. If your heater has old copper headers and replacing it is not in the budget, that is a genuine reason to wait. And if there is elaborate natural stone coping that cannot practically be sealed, the risk to the surround may outweigh the benefit.
None of those are permanent objections. They are reasons to fix something else first, or to time the conversion with a heater replacement or a resurfacing. The system will still be there next year.
Converting a chlorine pool to salt water: common questions
Can any chlorine pool be converted to salt water?
Almost any pool can. The conversion adds equipment to the plumbing rather than changing the pool itself, so inground, above ground, vinyl, fiberglass and concrete pools all work. The exceptions are practical rather than absolute: pools with certain unprotected metal components, some natural stone coping, older heaters without corrosion-resistant headers, and situations where there is no safe way to add a dedicated electrical circuit. Those are all worth checking before you buy anything.
Do you have to drain the pool to convert to salt water?
No, in almost every case you keep the water you have. You add salt to the existing pool and let it dissolve. The only reason to drain is if the water is chemically unusable, for example with stabiliser far above range, calcium hardness that is very high, or long-standing metal staining. A partial drain and refill is sometimes the cheapest way to reset those numbers before the generator goes in.
How much does it cost to convert a pool to salt water?
For a typical residential inground pool, expect roughly 800 to 2,500 dollars all in. The generator and cell are usually 500 to 1,800 depending on capacity and brand, the initial load of salt is 50 to 150 dollars, and professional installation including electrical work runs 300 to 800. Above ground pools sit at the low end, often 400 to 900 total, because the units are smaller and installation is much simpler.
How long does it take to convert a chlorine pool to salt?
The physical installation is a few hours. Balancing the water beforehand can take a day or two if anything is out of range, and the salt needs about 24 hours of circulation to dissolve and distribute evenly. Most people go from decision to a running system across a single weekend, then spend a week or so fine-tuning the generator output to hold the right free chlorine level.
How much salt do you need to convert a pool?
As a rough guide, about 250 pounds of salt takes a 10,000 gallon pool to 3,000 ppm from a near-zero starting point, which is six 40-pound bags, and a 20,000 gallon pool needs roughly twelve bags. Your existing water already contains some salt, often several hundred ppm if you have been using liquid chlorine, so always test first and calculate from the actual starting number rather than assuming zero.
Can you convert an above ground pool to salt water?
Yes, and it is one of the cheapest conversions because the systems are smaller and often plug into a standard outlet. The thing to check is the wall material. Steel-walled above ground pools can corrode where the liner is damaged or where water sits on the top rails, so a resin or hybrid pool is a better candidate. Keeping the salt at the low end of range and rinsing the top rails helps a great deal.
Will salt water damage my pool equipment or coping?
At 3,000 ppm the risk is real but manageable. Stainless rails and ladders, heater headers, some light rings and certain natural stone copings are the components that suffer. Modern heaters use corrosion-resistant headers, and sacrificial zinc anodes are cheap insurance for any pool. Sealing porous stone and rinsing splash areas covers most of the rest. The damage stories usually come from pools running well above the recommended salt level.
What size salt chlorine generator do I need?
Buy one rated for at least 1.5 times your actual pool volume, and 2 times if the pool is in a hot climate, gets heavy use, or has little shade. A generator sized exactly to your pool has to run at high output all season, which scales the cell faster and wears it out sooner. Oversizing costs a little more upfront and buys you a longer cell life and much easier chlorine management.
Do I need to shock the pool before converting?
You need clean, balanced water, and shocking is often part of getting there. Convert with clear water holding a normal chlorine residual, with no algae and no visible metal staining. Starting a generator in a pool with an algae problem just means the new system spends its first month losing a fight it was never designed to win on its own.
Is converting to salt water actually worth it?
It depends on what you value. The payback in chemical savings usually takes two to four seasons, so the money argument alone is thin. What people genuinely appreciate is not handling chlorine every week, water that smells and feels better, and a sanitiser level that stays steady. The trade-offs are more pH management, a cell to replace every few years, and some corrosion awareness. Most owners who switch do not switch back.
Can I still use my existing chlorine tablets after converting?
You can, but you should not use them routinely. Trichlor tablets add cyanuric acid with every dose, and a salt pool already runs a higher stabiliser target, so continuing with tablets will push it out of range and lock up your chlorine. Keep any remaining tablets for emergencies or use them up before you convert, and dose with liquid chlorine when you need a manual top-up instead.
Where exactly should the salt cell be installed?
Last in the return line, after the filter and after the heater, so it only sees clean filtered water and never sees the hottest water leaving a heater. Install it with enough straight pipe either side to fit unions comfortably, position it so you can remove it for cleaning without dismantling anything else, and follow the manufacturer’s orientation marking if there is one. Accessibility matters more than people expect, because you will be taking it out a couple of times a year.
The quick version
Converting a chlorine pool to salt water means adding a generator to the return line and salt to the water. You keep the pool full, you keep every other piece of equipment, and the whole job fits in a weekend for 800 to 2,500 dollars on an inground pool or 400 to 900 on an above ground.
Do it in this order and it goes smoothly: check your heater, coping and metals first, balance the water, buy a generator rated for at least one and a half times your pool volume, plumb the cell in last after the filter and heater, add salt broadcast across the deep end, circulate for 24 hours, then start at 50 percent output. Expect pH to climb in the first fortnight and be ready with acid.
Work out your salt load in the free pool salt calculator before you shop. Then read what your salt level should be, how to add salt properly, the ongoing maintenance routine, how to clean the cell, what it all costs long term, and whether salt really beats chlorine. More tools at waldev.com, and more of our work at waldev.co.
Safety and accuracy note: costs, equipment ratings and chemical targets given here are typical figures for residential pools in the United States and are provided for general guidance only. Always follow the installation manual for your specific salt chlorine generator. Electrical work on pool equipment must comply with local code and, in most jurisdictions, must be carried out or inspected by a qualified electrician. If you are unsure about any part of the installation, engage a licensed pool professional.
The Consumer Product Safety Commission publishes guidance on pool electrical safety, bonding and grounding requirements. CPSC pool and spa safety →
Check your local calcium hardness before converting, since hard fill water drives most salt cell scaling problems. USGS water hardness →
CDC Healthy Swimming covers the chlorine residual a pool needs to stay safe, whichever way it is produced. CDC Healthy Swimming →
The Pool & Hot Tub Alliance maintains the consensus standards for residential pool water chemistry and equipment. Pool & Hot Tub Alliance →