Pool Acid Wash in North Texas
Southern Pool + Outdoors handles pool acid wash jobs across North Texas. We drain the pool, wash stained or scaled plaster with diluted acid, neutralize it, and refill and balance the water so the fresh surface holds up. Call (214) 922-1914.
Stains or white scale that brushing won't touch? Get a free pool acid wash quote from Southern Pool + Outdoors.
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When Brushing Stops Working, an Acid Wash Can Reset the Plaster
Calcium carbonate is one of the main ingredients in plaster, and it’s the same mineral found in limestone. That’s why acid works on it. A controlled acid wash dissolves a very thin layer of the surface, and the stains and scale sitting in that layer go with it. What’s left underneath is brighter, cleaner plaster.
North Texas pools build up the kind of problems an acid wash fixes. Hard fill water and 100°F summers leave calcium scale at the waterline and on steps. Metal from corroded equipment can leave brown or blue-green stains. Old algae marks can stay in the plaster after the water has been clear for months.
An acid wash isn’t a cleaning you schedule every year, though. Every wash takes some plaster with it, so we only recommend one when the stain or scale is actually in the surface and the plaster is sound enough to take it. Some stains don’t need acid at all. Leaf stains usually bleach out with chlorine, and a green pool needs our green to clean recovery before anyone talks about plaster.
A pool acid wash from Southern Pool + Outdoors covers:
- Draining the pool with the right pump
- Checking the plaster for cracks, hollow spots and thin areas
- Washing the surface with diluted acid and scrubbing it
- Neutralizing the acid and pumping out the wash water
- Refilling and balancing the water for the fresh plaster
If the stains turn out to be at the tile line only, tile cleaning is the better fix. We’ll tell you which one you need before any water leaves the pool.
We Are Experts With:
What a Pool Acid Wash Actually Does
Muriatic acid is hydrochloric acid. Full strength, it sits around 31% and has a pH near zero, so it dissolves calcium carbonate fast. Plaster is built on calcium carbonate, which means a quick pass of diluted acid strips the top layer and everything stuck to it. Leave it on too long, or mix it too strong, and it eats into good plaster too. The whole skill of the job is taking off enough to clear the stain and no more.
Stains an Acid Wash Can Remove
The most common stains we see come from iron, copper and manganese. Copper usually comes from the pool itself. Most heaters have copper alloy in the heat exchanger, and water with low pH slowly dissolves it. That copper then leaves blue-green stains on plaster. Some copper algaecides cause the same problem. Iron shows up as reddish brown, and it comes from fill water or corroding metal parts. When copper meets high stabilizer levels, it can even leave a light purple stain.
Calcium scale is the other big one. It forms a crusty white deposit, often gray from the dirt trapped in it, and it builds up where water evaporates. In North Texas that means the waterline, the steps and the tanning ledge. Scale feels rough on feet, holds dirt, and gives algae a place to grip.
Black algae is a special case. It grows in spots with poor circulation, like deep corners and behind steps, and it roots into the pores of the plaster. Chlorine and brushing kill what’s on the surface, but the roots can survive and come back as the same dark spots. Taking off the top layer of plaster with the roots in it is sometimes the only way to stop the cycle.
Stains an Acid Wash Won't Fix
Dark brown patches under the trees are usually tannins from leaves, acorns and twigs. Chlorine often bleaches those out with no drain at all. Algae that is still alive is a sanitizer problem first. Washing plaster under a pool that will turn green again in two weeks wastes the wash.
Metal stains need one more step. If we don’t find where the metal is coming from, new stains form after the refill. So before we acid wash a metal-stained pool, we test the fill water and look at the heater and other metal parts. Otherwise you’re paying to remove stains that will be back by next summer.
Is Your Pool a Good Candidate for an Acid Wash?
Most plaster pools can take an acid wash when they need one. The question is if yours needs one now, and if the plaster has enough life left to give up a layer.
Signs It's Time
Look for these:
- Stains that stay after heavy brushing and normal chemical treatment
- White or gray scale at the waterline, on steps or on benches
- Old algae marks that never faded after the water cleared
- A blotchy, dingy color over the whole floor
- Rough plaster that snags swimsuits and scrapes feet
Spring is when most people notice. Oak pollen and storm debris settle on the floor, the water warms up, and stains that hid under winter water suddenly show.
When We'd Talk You Out of It
Each acid wash removes plaster and opens up its pores, which thins and weakens the finish. A pool can only take so many before it needs resurfacing. If your plaster is already pitted, chalky, delaminating or worn through to the gray base coat in spots, an acid wash will make it look worse. In that case we’ll tell you straight that the money belongs in new plaster.
Color matters too. Colored and pebble finishes don’t always come back even after a wash, because the color sits in the surface itself. Brushing won’t change it, and a second wash can reveal a different shade than you expected. We’d rather say that before we start than after.
Draining a Pool Safely in North Texas
An acid wash means draining the pool, and that’s the riskiest part of the job. An empty pool shell is a different structure than a full one.
Groundwater and the Hydrostatic Relief Valve
When the ground around a pool is soaked, the water in the soil pushes up on the shell. A full pool holds that pressure down with its own weight. Take the water out and a shell can crack, shift or, in a worst case, lift right out of the ground. Most pools have a hydrostatic relief valve in the lowest part of the floor. When groundwater pressure builds, the valve opens and lets that water into the pool instead of pushing on the shell.
We check that valve before draining and watch the weather. After a week of spring storms, the ground stays wet for a while, so we may hold off. Draining a pool on saturated ground just to keep a schedule is how shells get damaged.
Heat and Exposed Plaster
Heat is the other enemy. Plaster that sits empty in direct sun on a 100°F afternoon dries out and can crack. That’s why we keep the empty time short and keep the plaster wet while we work. In the hottest weeks of summer, we schedule around the heat when we can.
Our Pool Acid Wash Process, Step by Step
Every acid wash follows the same order, adjusted for your plaster, your equipment and the stains we’re after.
Inspection Before Anything Drains
We look at the stains, the plaster and the equipment first. That’s when we test for metals, check the hydrostatic relief valve, and decide if acid is the right tool at all. Then we drain the pool with a pump sized for the job and pull out the debris left on the floor.
Washing the Plaster
We start with the pump and filter shut down and the plumbing protected, so acid can’t reach the equipment. Then we apply diluted muriatic acid in sections, from the top of the walls down. The acid foams as it reacts with scale and stains. We scrub as it works and rinse each section quickly, because the contact time decides how much plaster comes off. Several light passes beat one strong one.
Safety gear isn’t optional. Acid fumes burn eyes and lungs, so the crew wears eye protection, gloves and a respirator rated for acid gas. Acid and chlorine also never share a bucket, a sprayer or a pass. The CDC warns that pool chemicals can injure people when mixed together, so every chemical goes in on its own.
Neutralizing and Cleanup
Once the wash is done, the acid water that collects in the deep end gets neutralized with soda ash. Then we pump it out, rinse the whole surface again, and clear the last of the wash water. We dispose of it following local rules. Leftover acid that stays in a low spot will keep etching, so this step gets as much care as the wash itself.
Refill and Water Balance
We refill as soon as the surface is clean, then test and balance the water right away. Freshly washed plaster is porous, and it reacts to water chemistry fast. Water with low pH, low alkalinity or low calcium is corrosive to plaster and can etch it within a short time. Water that runs high on all three drops scale right back on. We aim for calcium hardness in the 200 to 400 ppm range and balance the rest with the Langelier Saturation Index.
Acid Wash vs. Chlorine Wash
These get mixed up a lot, and the difference matters. A chlorine wash uses strong chlorine on a drained surface. It kills algae and bleaches organic stains, but it doesn’t remove plaster. An acid wash removes a layer of plaster to take out mineral stains and scale.
Our Drain & Clean service uses a chlorine wash. It includes draining the pool, a chlorine wash, equipment and filter cleaning, refilling and chemical rebalancing. That’s often the right call for a pool that sat neglected or held old algae. When the problem is metal or calcium in the plaster, acid is the tool. Some pools need both, a chlorine wash for the organics and a targeted acid wash for the mineral stains. We’ll tell you which job fits after we see the pool.
Keeping Stains From Coming Back
An acid wash fixes what’s already there. Water balance decides how long the plaster stays clean afterward.
Hard water is the main reason scale returns here. Evaporation through July and August concentrates calcium, and each top-off adds more. Keeping pH and alkalinity in range slows scale even when calcium runs high. Metal stains come back when the source is still there, so keep pH out of the low range that dissolves copper. Brushing matters as well. Scale and stains get much harder to remove the longer they sit, and regular brushing knocks them loose early.
Most homeowners hand this off. Our weekly pool service keeps the water balanced after an acid wash, and you get a digital service report with chemical readings after every visit. That’s the cheapest way to make the wash last.
Why Homeowners Choose Southern Pool + Outdoors for an Acid Wash
We inspect the plaster before we drain, we find the source of metal stains before we wash, and we tell you when an acid wash isn’t worth doing. Your plaster only has so many washes in it, and we treat it that way.
You don’t need to be home while we work, as long as we can reach the pool and equipment. If your plaster looks stained, scaled or dull, call (214) 922-1914 or schedule an acid wash assessment online. You can also see our other specialty services for jobs that fall outside a weekly visit.
Our Service Areas
- Allen
- Plano
- Dallas
- Mckinney
- Wylie
- Anna
- Fairview
- Prosper
- Lucas
- Celina
- Carlton
- Melissa
Pool Acid Wash Questions From North Texas Homeowners
Here are straight answers to the pool acid wash questions homeowners around North Texas ask most often.
An acid wash removes a very thin layer of plaster, and the stains and scale in that layer come off with it. It works on mineral stains from iron, copper and manganese, calcium scale and old algae marks. In North Texas, where hard water leaves scale at the waterline, it can bring dull plaster back to a brighter, even color.
The cost depends on the pool's size, the type of finish, how heavy the stains are, and the water to refill it. A small pool with light scale is a different job than a large one with years of metal stains. Call (214) 922-1914 and we'll look at the plaster and give you a quote before any water is drained.
The wash itself usually takes a day. Draining and refilling add more time, depending on the pool's size and your water pressure. We keep the pool empty for as short a time as we can, because plaster sitting empty in North Texas sun can crack. Then the water gets balanced as soon as the refill is done.
You can, but it's one of the riskier pool jobs to learn on. Full strength muriatic acid fumes, burns skin and eyes, and etches plaster if it stays on too long. Draining also carries risk when groundwater pushes up on an empty shell. If you try it, wear an acid gas respirator, eye protection and gloves, and never let acid touch chlorine.
No, not on a schedule. An acid wash is a fix for stains and scale that brushing and normal chemistry can't remove. Every wash removes some plaster, so doing it as routine maintenance shortens the life of the finish. Plenty of North Texas pools never need one when the water stays balanced and the walls get brushed.
Yes, to a degree. Each acid wash dissolves a thin layer of plaster and opens its pores, which thins and weakens the finish over time. One careful wash on healthy plaster costs very little of its life. Repeated washes, or washes on plaster that's already worn, bring resurfacing closer. That's why we don't recommend acid as routine maintenance.
Usually not. Acid opens the surface further, so pitted or chalky plaster tends to come out of a wash rougher than it went in. A chlorine wash and a power wash are gentler options for cleaning a worn surface. If the plaster is that far gone, the honest answer is often resurfacing, and we'll say so before you spend money.
It can be, with care. Plaster left empty in direct sun can dry out and crack, so we keep the empty time short and keep the plaster wet. The bigger risk in North Texas is wet ground after spring storms, when groundwater can push up on an empty shell. We check the hydrostatic relief valve first.
It is if the plaster is sound and the problem is mineral stains, scale or old algae marks in the surface. White, spotty areas are often calcium. It isn't a good candidate if the plaster is pitted, delaminating or worn thin. We check the finish and test for metals before recommending a wash, so you know the result will last.
Only a few hours, and never more than about a day. Lowering the whole pool's pH to strip stains without draining can over-etch plaster and leave it sandy and cloudy. If stains haven't changed in the first hour or so, they likely won't. A no-drain treatment needs close testing and a fast return to balanced water.
Still have questions?