Does CLR remove calcium from pool tile?

CLR can remove calcium deposits on pool tile, but it is not recommended. CLR is a household cleaner with strong acids that can damage grout, etch certain tile finishes, and discolor surfaces, and residue left in the pool can affect water chemistry. A pool-specific tile descaler is a safer choice.

Does shocking a pool raise calcium hardness?

Shocking a pool usually does not raise calcium hardness directly when using chlorine-based shock with sodium hypochlorite or lithium hypochlorite, but calcium hypochlorite shock does add calcium and will raise calcium hardness over time. Repeated use of calcium-based shock is the main cause of hardness creep in pools. Shock types and their effect on calcium: - **Calcium hypochlorite (cal-hypo)** — adds calcium, raising hardness by roughly 5-7 ppm per 1 ppm of free chlorine added - **Sodium dichlor** — adds minimal calcium, but lowers pH slightly - **Liquid chlorine (sodium hypochlorite)** — adds no calcium - **Lithium hypochlorite** — adds no calcium, though it is more expensive If your calcium hardness is already high, switch to a non-calcium shock.

How do you clean calcium deposits on pool tile?

Calcium deposits on pool tile are usually removed with a mild acid-based tile cleaner or a pumice stone, applied carefully so you don't damage the grout or glaze. In Arizona's hard water, scaling builds up quickly, so periodic cleaning is important. The typical process includes: 1. **Test water chemistry** — Confirm pH and calcium hardness so you know whether the scaling is caused by imbalance 2. **Apply a pool-safe tile descaler** — Use a product made for pool tile, following label directions and wearing gloves 3. **Scrub gently** — Use a nylon brush or pumice stone; avoid steel wool, which scratches tile 4. **Rinse thoroughly** — Remove all residue and rebalance the water afterward For heavy scale, a professional acid wash or tile service is often more effective and avoids damage.

How to remove calcium from a pool without draining?

You can remove calcium from a pool without draining by using a commercial calcium remover or scale dissolver, a partial water replacement, or a combination of both. Dissolvers work by lowering pH and bonding with calcium so it can be filtered out or scrubbed away. Partial draining (replacing 10-25% of the water) lowers overall calcium hardness with less cost than a full drain. A typical process: 1. Test water for calcium hardness, pH and total alkalinity 2. Lower total alkalinity to around 80-100 ppm and pH to 7.2-7.4 3. Add a calcium/scale remover according to label directions 4. Brush tile and surfaces, then run the filter for 24-48 hours 5. Retest and replace water if calcium hardness is still above 400 ppm Plaster pools need extra care, since strong acids can etch the surface. Hire a pool professional if scale is heavy or on plaster.

What causes calcium buildup on pool tile?

Calcium buildup on pool tile is caused by calcium carbonate scale that forms when water is hard (high calcium hardness) and has a high pH or high total alkalinity. In Phoenix-area pools, the combination of hard municipal water, intense sun and heat driving evaporation, and frequent chemical additions concentrates calcium at the waterline, where it precipitates out and bonds to tile. The main contributors are: - **Hard source water** — Phoenix-area water often tests 200-400+ ppm calcium hardness, well above the ideal pool range of 200-400 ppm - **High pH (above 7.8)** — makes calcium less soluble and encourages scale to form - **High total alkalinity (above 120 ppm)** — buffers pH upward and increases scaling tendency - **Evaporation** — leaves minerals behind, especially in summer heat - **Over-use of calcium-raising chemicals** — some shock and pH products add calcium or push levels higher Regular testing and balancing pH, alkalinity and calcium hardness, plus prompt tile cleaning, prevents most buildup.

What is a good calcium dissolver for pools?

A good calcium dissolver is a non-acid, phosphate-free or chelating scale remover that is safe for plaster, tile and equipment. Products based on EDTA or citric acid blends are commonly used, and liquid formulas tend to be easier to dose than powders. Always pre-test water and follow label directions, since over-dosing can cause staining or cloudy water. Common options: - **Liquid scale and stain removers** — fast-acting, good for tile and waterline ($15-$35 per quart) - **Citric acid-based dissolvers** — gentler, lower-cost option for light scale ($10-$25 per pound) - **Muriatic or dry acid** — strongest option, reserved for heavy scale and only on fiberglass or vinyl, not plaster ($10-$20 per gallon) For Phoenix pools with hard water, a chelating scale inhibitor used regularly can prevent buildup.

What removes calcium from tiles?

Calcium is removed from tiles with mild acid-based cleaners, vinegar for light deposits, or commercial tile and grout descalers for heavier buildup. Gentle scrubbing with a non-abrasive brush or pumice helps lift the scale. Common options include: - **White vinegar** — Good for light deposits, low cost (about $3-$5 per gallon) - **Commercial tile descaler** — Stronger, suited to heavy scale ($15-$35 per bottle) - **Professional tile cleaning** — Best for large areas or delicate stone ($150-$400 for a typical pool) Always test on a small area first and rinse thoroughly.

What will dissolve calcium buildup?

Calcium buildup dissolves most effectively with mild acids such as muriatic acid, citric acid or a commercial scale remover, applied to the scale and scrubbed off. Chelating agents like EDTA also work on lighter deposits without strong acid. Stronger acids work faster but carry more risk to plaster, grout and equipment. Options include: - **Citric acid** — safe for most surfaces, slower on heavy scale - **Commercial scale remover** — formulated for pool use, balanced for surfaces - **Muriatic acid** — fast and strong, but etches plaster and must be diluted and applied carefully - **Professional acid wash** — best for heavy, widespread scale, typically $300-$700 in the Phoenix area Always test water and wear protective gear when working with acids.

Pool Acid Wash Cost: What Phoenix Homeowners Should Expect

How much does a pool acid wash cost in Phoenix?

Phoenix-area pool companies' own websites, checked October 2026, list acid washing at $479, and an acid wash with a power wash at $550. Several others print entry prices, with "start at $400" the most common. One Phoenix company's guide says a standard acid wash typically runs $300 to $700^[1], and another says $350 to $700 for a job that includes draining, applying acid, scrubbing, rinsing and neutralizing^[3].

Worker rinsing the walls of a drained pool — A drained pool being rinsed during an acid wash

Those numbers apply to pools in Mesa, Scottsdale, Chandler and Gilbert alike. They don't all cover the same work.

Drain and refill is often priced separately. A drain and refill is usually priced as a single service, and the final cost depends on the water heater's size and access.

Several factors explain the wide spread. Quotes bundle different things: draining, the wash itself, a power wash, chemical rebalancing, refill and sometimes an attached spa.

Compare like for like, and ask for a line-item written quote. For what the job involves, see How to Acid Wash a Pool (and When to Call a Pro).

Prices last checked October 2026, from Phoenix-area pool companies' websites and the cited guides.

Choosing between acid wash, tile cleaning and tile replacement

Start with what you can see, not with a price. Phoenix tap water is very hard, at 300+ ppm calcium carbonate, so white crust on the waterline is usually calcium deposit rather than a plaster problem.

That is why tile cleaning is often a separate service from an acid wash.

Service	What it fixes	Typical Phoenix-area price range	What moves the price	Right choice when
Acid wash (drain and wash)	Stained, dull or lightly scaled plaster	$300 to $700 per one Phoenix company's guide^[1]; $350 to $700 per another^[3]; refill extra	Drain and refill, pool size, spa, surface type and age	Plaster is sound but discolored
Pool tile cleaning (calcium removal)	White crusty scale on waterline tile	$295 to $495 per one Phoenix guide^[1]; one company lists from $249 with a 40-foot minimum^[2]; another lists $7.50 per linear foot	Linear feet of tile, scale severity, method, access	Tile is intact but crusted
Pool tile replacement	Cracked, loose or missing tile	$10 to $25 per tile installed; $350 to $800 for a small repair; $3,000 to $8,000 or more for full waterline replacement^[1]	Linear feet, tile material, bond beam condition	Tile has physically failed

Prices last checked October 2026 and in 2026 guides; cleaning methods vary by company.

A plain test

White crusty scale on tile: tile cleaning.
Stained or rough plaster: acid wash, if the surface is sound.
Cracked, loose, hollow or missing tile: replacement.

Calcium on tile is often handled by bead blasting or specialty cleaning rather than acid.

Price range

Typical Phoenix-area price ranges

A bar with a break runs past the scale; its full range is written above it.

Typical Phoenix-area price ranges
Item	Low	High
Acid wash	$300	$700
Tile cleaning	$295	$495
Small tile repair	$350	$800
Full waterline replacement	$3,000	$8,000

For diagnosis and quotes, see Pool Tile Repair and Calcium Removal, or read about calcium buildup on pool tile.

Price swings come from drainage, surface and crew workload

Three things move most quotes: whether the pool gets drained, what the surface is made of, and how much work the crew faces.

Price factors

What changes the price

Drain and refill
Adds labor and water cost
Surface type and age
Thin or aged finishes carry more risk
Pool size and access
Spas, steps and tight yards add time

Drain and refill

Draining adds labor, and refilling adds water cost. One Phoenix company's guide says refilling 10,000 to 20,000 gallons commonly adds $50 to $150 to the water bill, depending on the utility and tier reached^[3].

Each city sets its own water rates. Your cost is gallons times your utility's rate.

Ask who handles the drain and where the water goes. Also ask whether groundwater is a concern before the pool is emptied, and how the crew will handle summer heat on an exposed surface.

Pro tip

Ask each contractor to price draining, discharge and refill as separate lines so quotes compare fairly.

602 Pool Pros

Surface type and age

Plaster, pebble and quartz react differently to acid. Thin or aged surfaces carry more risk, because a wash removes a thin layer of finish.

Some contractors use a chlorine wash on pebble instead of acid. Ask which method applies to your finish. For the finish differences, see Plaster vs. Pebble Pool Finish.

Pool size and access

Larger pools, attached spas, raised walls, spillways and steps all add time. So do tight side yards, a high tile line and repeat visits for stubborn scale.

Tile replacement scales with the linear feet of waterline, the tile material and whether the bond beam is damaged. Demolition can expose problems that weren't in the first estimate.

When an acid wash beats replastering

An acid wash is mostly cosmetic. It suits sound plaster with stains or scale.

It does not suit surfaces that are delaminating, etched or rough from wear, because there may be little finish left to give.

Two cases

Acid wash or replaster

Case A: Acid wash

Sound plaster
Stains or scale

Case B: Replaster

Delaminating surface
Etched or rough from wear

A wash on an aged or pebble surface can leave it rougher or expose aggregate, and then the pool needs resurfacing anyway. You end up paying for both.

Before you agree to anything, ask the installer: "What is my surface, how old is it, and what happens if it doesn't tolerate acid?"

If the finish is worn, compare the wash against resurfacing before you drain. Pool Resurfacing Cost in Phoenix breaks down that budget, and Pool Resurfacing and Replastering covers the work itself.

Licensing matters here too. The R-6 classification covers servicing and minor repair of residential pools and accessories^[4].

Complete replacement of plaster or pebble interiors falls outside that scope. A wash that reveals a failing surface can move the job to a different license class and a much bigger quote.

How to hire a licensed pool pro and get a fair quote

Work through this checklist before you sign:

Check the license class. Arizona requires an Arizona Registrar of Contractors (ROC) license. R-6 or CR-6 covers service and minor repair. B-5, B-6, KA-5 or KA-6 cover broader work^[4]^[5]. Look the contractor up on the ROC Contractor Search at roc.az.gov and confirm the class matches your job. Contractors must be properly licensed before submitting bids^[4].
Get a written contract over $1,000. It should state the license number, price, payment terms and the ROC complaint notice. Don't pay cash without a signed receipt, and don't let payments run ahead of the work.
Know your cancellation right. Door-to-door sales carry a three-business-day cancellation window, and the ROC warns about low-price door knockers.
Don't read too much into "licensed, bonded and insured." The ad doesn't prove insurance. ROC requires only workers' compensation, so ask for the certificate. See Is 'Licensed, Bonded and Insured' Enough in Arizona?.
Get three itemized quotes. Each should separate draining, discharge, the wash, tile cleaning, refill, startup chemicals and any repairs.

Permits differ by city. Ask the contractor whether your city requires one, and have the contract say who pulls it.

For more, see Questions to Ask Before Hiring a Pool Contractor.

Pool acid wash cost FAQ

How long does it take to acid wash a swimming pool?

Most of the job is draining, washing and rinsing, then refilling and rebalancing. The wash itself is much shorter than resurfacing or tile replacement, but draining and refilling stretch the timeline.

How to Acid Wash a Pool has the step-by-step.

How expensive is it to drain and refill a pool?

Drain and refill pricing in Phoenix varies by company, so compare a few written quotes. Refilling 10,000 to 20,000 gallons commonly adds $50 to $150 to the water bill^[3].

How much acid do you put in a pool?

Amounts depend on the pool, the surface and the product, so leave this to a pro. Acid is hazardous to handle and can damage a surface if misapplied.

Follow the manufacturer's label and safety guidance, and see the how-to guide for when to call a professional.

How do you clean a severely dirty pool?

If the problem is algae, you likely need a green pool cleanup, not an acid wash. Start with Green Pool Cleanup and Water Treatment or the green pool cleaning steps.

Green-to-clean recovery is priced separately, so ask for the quote in writing.

Can you acid wash a pool with water in it?

A standard acid wash is done on a drained pool. Draining carries its own risks, including groundwater pressure on concrete pools and surface exposure in summer heat.

How much does pool tile cleaning or replacement cost?

Cleaning ran $295 to $495 in one Phoenix guide^[1], and one company lists $7.50 per linear foot. Replacement runs $10 to $25 per tile installed, $350 to $800 for a small repair, and $3,000 to $8,000 or more for full waterline replacement^[1].

For a diagnosis, see Pool Tile Repair and Calcium Removal.