How To Remove Calcium Buildup From Your Swimming Pool

by T. Duff on February 6, 2009

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How To Eliminate Calcium Deposits From Your Swimming Pool…

If you are experiencing a calcium buildup (scale) along the water line of your pool there are a few things to consider doing.

1.  Keep the calcium harness levels below 350 PPM.  If it gets beyond this, drain the pool down (not a fiberglass) half way and replace the water.  There are sequestering agents available to reduce calcium levels, however, they’re not cheap. 

2.  Keep your pH levels between 7.4 and 7.8.  Keeping your chems in check will drastically prolong the amount of time it takes to accumulate calcium buildup. 

Here’s where “manual” labor kicks in…

1.  For a fiberglass pool grab a polyblend brush (wire brush for plaster or pebble).

2.  Take muriatic acid and mix with water – 2 parts acid to 1 part water.

3.  “Sponge” the solution directly on the calcium deposit.  It will run into the water itself – no big deal. 

4.  Take your brush and begin brushing off the calcium – the thicker and longer it’s been there, the more difficult it will be to remove.  Key here is once you begin seeing the white, chalky buildup, eliminate it before the calcium deposit gets out of hand.  You may also want to use a razor…

I’ve also been really happy with other alternatives such as glass bead, epsom salts and sand blasting calcium removal methods - they work like a champ, however, it can be a costly process (most companies charge between $3 and $5 per foot – this is gauged upon the perimeter of the pool).

Both of these methods are designed for plaster and pebble surfaces, however, epsom salts should be safe for a fiberglass surface without any issues (make sure they “test” a small area first as I have not used epsom on a fiberglass pool).

:)

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{ 69 comments… read them below or add one }

cybersherrif March 6, 2009 at 8:28 am

I have an in-ground vinyl lined pool. The only metal in contact with the water is a stainless steel ladder. All other parts are either polymer, plastic or are coated to prevent corrosion as with the heat exchanger in the heat pump. Why do I need to worry about hardness levels? There is nothing for softer water to attack. No gunite or metals. Doesn’t calcium hardness simply add to your TDS levels, which in turn adversely affects your chemical levels…as with chlorine? Am I missing something?

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fireyourpoolguy March 6, 2009 at 9:32 am

Good question…

TDS and calcium hardness go hand in hand…

The primary issue is that when either one (or both) are high, the water becomes aggressive or nonreactive. So, you continue dumping more and more chemicals in the water only to have a minimal impact – the end result is adding more chems than necessary to get things into alignment (and throwing money away).

Hope this helps.

Terry

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Wyn Mullinax March 15, 2009 at 12:25 pm

What would U suggest to clear/clean
calcium buildup on exterior of Sand Filter,
w/o damaging equipment?

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fireyourpoolguy March 28, 2009 at 8:48 am

Hi Wyn,

Use a metal small brush…similiar to what you use to scrub algae. If this by itself does not eliminate the calcium buildup, use a muriatic solution with water and scrub. Should have no problems removing the calcium buildup.

Cheers.

Terry

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dawid April 14, 2009 at 8:48 am

I have a fibre glass swiming pool and my calcium harness level is 1000ppm. How can I lower this to under 300ppm? I also have a salt chlorinater connected to my system.

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fireyourpoolguy April 14, 2009 at 10:49 am

Good question…

There are a few directions to help bring it down. With a fiberglass pool, draining is not an option, however, one could backwash it down to the skimmer several times over a few weeks to dilute the water…bringing down calcium levels.

You can also treat the water by using tri-sodium phosphate.

Best,

Terry

:)

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Fritz April 23, 2009 at 7:52 am

How about calcium buildup on the plaster? The local pool company told me that an acid wash would damage the plaster and would not remove the rough calcium. Is this true?

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fireyourpoolguy April 23, 2009 at 8:04 am

Good question Fritz…

Typically, an acid bath can remove calcium buildup from the plaster – it takes some elbow grease. Don’t be afraid to use a firm brush. There’s a lot of variables here…if it’s too thick and been there for some time, it may require a glass bead treatment.

This is very effective and runs about $4/per linear foot of the pool – this can vary a little depending in different parts of the country.

The entire purpose of an acid wash is to strip a very thin layer of plaster from the surface…exposing a new, fresh layer of plaster. So, yes this can, over time, damage plaster (it reduces it’s “thickness”) – an acid wash can safely be done several times without requiring a replaster.
(which is pretty expensive).

Hope this helps.

Terry

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may powers May 21, 2009 at 8:08 am

We have a plaster pool. The hardness has gone up from 400 to 500 from 3 weeks ago after superclorination and algeacide treatment after the rain. What is the best way for me to lower the hardness at this time, except from draining the pool. Last year it was always within range, in fact it was even low first part of the year. Does the granular shock ever raises the build up of calcium?

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fireyourpoolguy May 28, 2009 at 8:43 am

Good question May,

Unfortunately, there’s really no effective way to reduce calcium hardness other than draining pool (or a partial drain or even backwash several times over a week period).

Hypochlorite contains calcium…contributing to what you’re experiencing.

Terry

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Inge gden July 12, 2009 at 4:38 pm

Is there a way to clean calcium from tile on the pool without going to the expense of bead blasting can you use a solution of muriatic solution
thank You

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fireyourpoolguy July 23, 2009 at 3:48 pm

Hi Inge,

The answer is yet, but my response probably thrill you…

I would recommend using a pumice stick. It’s labor, but that’s the trade off to save some $$

All the best,

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Renee August 17, 2009 at 10:38 pm

You mentioned using tri-sodium phosphate in an earlier post. Can it be used in a quartz pool to reduce calcium hardness? If so, in what proportions? Do the particles just remain suspended increasing the TDS?

Thank you!

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fireyourpoolguy September 3, 2009 at 11:26 am

Hi Renee,

When trisodium phosphate is added, it essentially bonds with the calcium (or TDS) in the water. The net effect is to neutralize the material to avoid the pitfalls calcium brings to a body of water when it’s elevated. It can be used in a quartz pool without any issues.

Best,

Terry

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Chris July 8, 2010 at 9:42 pm

I like your straight forward, common sense, answers. Thanks.

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fireyourpoolguy July 21, 2010 at 7:54 am

Many thanks Chris.

:)

Terry

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carla May 17, 2012 at 12:55 am

thanks so much for your aloha. Iwas wondering if a pneu-power drill with a wire brush could take off scale with lime-away?

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LARRY September 13, 2010 at 10:19 am

I HAVE A VINYL LINED POOL, 16X32 W/ 9′ DEEP END. i HAVE A WHITE COVERING ON THE LINER ALL OVER IN BOTH THE DEEP AND SHALLOW ENDS. IT LOOKS “CAKEY” IN PLACES, LIKE A BUILD UP OF SOMETHING. I HAVE BEEN TOLD THIS MAY BE CALCIUM. I HAVE ATTEMPTED TO BRUSH BUT NOTHING IS RESOLVED BY THIS. IF IT IS CALCIUM WHAT WOULD BE THE BEST WAY TO CLEAN? THANKS

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Traci June 2, 2011 at 9:56 am

I have this same problem. I need an answer too. If you get one will you let me know? Good Luck

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Michael February 11, 2011 at 1:42 pm

Small flakes are on the bottom of our pool and coming into the tubes of our pool heaters. We had these tested and said they were calcium deposits. We are getting a second opinion and sending to a lab. We are using Heatsavr to help reduce energy costs by eliminating some of the water evaporation. Our chemicals are liquid, chlorine and magic acid, and auto fed into the pool. Our alkalinity was low at times and we got a handle on that. Our calcium is at 600 ppm which is high, TDS is at 2000, PH 7.7, Chlorine at 3.0. These flakes have been eating our heaters up and the heaters are only 14 months old. I assume dumping the water is ideal but we are in season and it would not happen until summer or fall.

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Melissa February 20, 2011 at 12:39 pm

We just purchased a house and the pool has been sitting, unmaintained, for years. There is a calcification all along the tiles and walls of the pool. It is a quartz pool. Can we remove this ourselves, or do we need to hire a professional? What are our options?

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fireyourpoolguy February 22, 2011 at 11:34 am

@ Melissa,

Ugh…no fun. You can use a pumice stick – it really depends on how thick the calcium buildup is. It’s a lot of work too.

I’d recommend at least getting a couple quotes from tile cleaners – preferably one who uses the “glass bead” method.

Terry

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kimberly March 23, 2011 at 5:14 pm

We spent $50,000 remodeling our backyard last summer and gutting a gunite pool with fiberglass walls. We have calcium buildup. Can we paint over it? Will it bleed back through? It has never done this when it was a “redneck inground pool” but now that we have spent so much on it we hate that a lot of it looks white and some is blue. What are our options? I was also told that it can ruin your pool and pipes. I spent a lot of money at fox pool supposedly getting it on track but when we took the cover off today, it possibly looks worse:( HeLp, PlEaSe!!!!

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Robert March 27, 2011 at 12:33 am

I ‘m having a problem with calcium deposit buildup on the moss rock around our pool. It’s a salt system and don’t know what to use to get this white scale deposit off. Can you recommend a product or a solution to my problem.

Thanks

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fireyourpoolguy March 27, 2011 at 7:04 am

Hi Kimberly,

Way too soon for something like this to be taking place. Check and confirm that the water is balanced…TDS and pH issues can cause this (as well as a couple others, but these are the most common). I would recommend having a glass bead treatment done….that’ll make ‘er look all nice and perty again.

Also, be sure to treat the cause and not the side effect..if the other issue isn’t addressed you’ll create this yo-yo cycle…and make donations every year.

Terry

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fireyourpoolguy March 27, 2011 at 7:04 am

Hi Robert,

It’s unliklely that any solution is going to be very productive. Couple of options…

1. Get a glass bead tile treatment – this is a great way to bring it back to a “near new” state.

2. A good ‘ol fashion pumice stick – labor and intense…not much fun, but it’ll get the job done and save a few bucks.

Terry

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cheryl April 1, 2011 at 3:55 pm

I have a plaster pool and we got it resurfaced. I have swept the pool everyday and cleaned the filter but I just noticed that clacium is all over the tile and steps and the pool light. I can’t believe that I haven’t seen it before. It is really bad. I am trying to find the cheapest way to take care of this as resufacing the pool broke me. Please help!
Cheryl

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fireyourpoolguy April 4, 2011 at 8:04 am

Hi Cheryl,

I can understand the frustration. I’d recommend using a pumice stick – it’s work, but it typically gets the job done…and you won’t break the bank.

Terry

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John April 7, 2011 at 7:57 pm

I have calcium buildup on my tile like many people. The water is four years old and I am going to drain in a few weeks. I was told that I could use CLR or LimeAway to remove the calcium, then drain the pool and start out fresh. Is this true or will I make a disaster?

Thanks,

John

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Nicole April 10, 2011 at 11:18 am

I have a plaster pool and have recently noticed very hard bumps (I am assuming calcium deposits) ALL over the pool walls. The Ph is always high but the alkalinity is always low so it is a constant battle to lift one and lower the other at the same time. The calcium did not begin to appear until I began adding a good dose of alkalinity increaser. What would you recommend to do and how can I remove the calcium from the entire pool with out draining?

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fireyourpoolguy April 10, 2011 at 11:46 am

@ John,

I’ve never had any luck w/ CLR for this application – although it does wonders for basic pump cleaning. The calcium buildup would have to be VERY light for it to have an impact.

Best way to deal w/ calcium is a good ‘ol pumice stick or a glass bead tile clean.

Terry

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Blake April 11, 2011 at 12:12 pm

How about calcium buildup (like rough and bumpy) across all the walls of the pool- not just the tile? Would glass bead work for this application? Or would I need to use a polisher similar to Aquaglide?

And if using glass bead what pressure PSI/ CFM and type of glass are they using? Med or small glass– and how do they get rid of it- vac it up with a shop vac.

Any other ideas would be appreciated.

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Josh April 14, 2011 at 9:13 am

I have a 14,000 gallon in-ground pool with a vinyl liner. It was not covered and winterized last year and the pump did not run during the winter. The pH level went higher than 8.4, alkalinity was relatively low at 50ppm, and calcium levels were about 130ppm. When I started to restore the pool this spring, their was an obvious algae problem (since the pool was dark green) and a scaling problem. The scale went from the water line down to the bottom of the pool walls. It is white, coarse, and very hard to scrub off. I’ve used cholorine and algecides and the pooland it is not green anymore, but VERY cloudy. I’ve used clarifiers, flocs, metal controls, etc. to no avail. And I still have the scale buildup. What is the best way to remove this scale? Also, could it be contributing to the cloudy water? Perhaps the sand filter is scaled up too? Please help.

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fireyourpoolguy April 14, 2011 at 9:26 am

@ Josh,

The excess calcium is likely not the reason for the cloudy water – that’s the result of all the “stuff” that’s been added to the pool. I’d recommend using a good water clarifier and get the pH/TA dialed in (this can also contribute to the cloudy water).

Let the equipment run 24/7 and backwash frequently to help speed up the process as well. Circulation is key to getting the water clear.

On the scale, I wouldn’t recommend using chems – they’re not worth the $$ unless the buildup is VERY light. Consider doing a sand blast or glass bead method to remove the existing calcium.

Terry

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fireyourpoolguy April 14, 2011 at 9:45 am

@ Blake – this is the ideal scenario for considering glass bead. For pool tiles, you don’t want it to exceed 40 PSI. For plaster or pebble you can go a bit higher (I wouldn’t exceed 75psi as it may do damage). I’d recommend using a #8 or 10 mesh – it’s pretty fine and will fit through the whole in a sewing needle.

Assuming there’s water in the pool, use portable equipment – replace where the cartridge filter would be with mesh bag to collect the beads. If the pool is empty a shop vac will do the trick.

Terry

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John April 16, 2011 at 10:15 am

I bought a house with a pool, not sure what I’ve taken on.
Total Calcium is 1500 ppm, probably because the make up water is from a well which is also 1500 ppm. I have severe scaling on all surfaces. Water is clear, but I have few black algae spots that are getting worse, algaecide and chlorine seem ineffective, pH is difficult to keep low, seems to want to settle around 8.0

I understand my only option is to drain and refill, but it is pointless to refill from the well. I can refill from a city water source which is 180 Total calcium, or should I pay to truck in water with less Calcium? It’s a large pool, 50,000 gallons, I don’t think I want to spend the money on partial drain and fills to lower the TC, it will cost around $400 to fill from the city water line.

While the pool is drained, should I have it acid washed to remove the scale buildup? Will the scale ‘dissolve’ over time if the pool is refilled with TC 180 or lower?

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fireyourpoolguy April 20, 2011 at 12:22 pm

@ John,

A few things going on…

The scale buildup needs to be addressed or it will be there indefinitely.

Use city water…180ppm is fine and won’t cause any issues. I would remove the scale with a thorough acid wash (may not do the trick though). You may need to have a glass bead calcium removal done – depending on the severity/thickness of the buildup.

Terry

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John April 21, 2011 at 7:31 pm

I have a customerbthat just had a pool built. A few weeks in when they started using it they noticed that there was some sort of buildup on walls , tiles and light. What is this from and how do I help them fix it. It has a light pebble finish and heard its possible that it wasn’t cleaned before filling with water or acid washed properly. It is a salt system.

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Jason April 25, 2011 at 10:46 pm

Where can I find a media blaster fairly cheap? I’ve heard Harbor Freight carries some inexpensive one for under $100. They are sell glass beads in 25lb bags. I was also thinking about using the pumice bloks sold at Leslies Pool supply. I was told to soak them 1 hr prior to use. Would this work best with their “de-scaler’ paste, muratic acid mix 2/1, or no chemicals at all and just srub away?
Thanks for any advice.

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fireyourpoolguy April 26, 2011 at 8:30 am

Hi Jason,

Not all calcium is created equally – initially, try using the pumice stick without any chemicals. If it’s too stubborn and not coming off, use a 2:1 acid/water mix from a spray bottle or apply with a sponge.

Those blasters are sufficient – make sure you’re not spraying at speeds greater than 40 psi. I prefer using glass beads, but you can also use mineral salt – they’re a bit softer and the process may take a bit longer.

Terry

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fireyourpoolguy April 26, 2011 at 8:35 am

@ John,

It’s challenging to decipher exactly what’s taking place with limited info. That’s really soon to be having any type of calcium buildup. First thing I’d do is to check the water source and test for TDS & calcium. Also, have the water tested for iron and copper – elevated counts can result in staining.

Sorry for the vague response – if you can provide more info on buildup or pics I can better assist.

Terry

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Todd Stewart June 2, 2011 at 7:48 pm

Hi, We have a 3 year old 35,000 plaster pool. This year I noticed a lot of staining on the floor and stairs. After closer inspection I realized it was rough like sand paper. My local pool store said it was calcium scaling. How do I get rid of this mess.

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Karen June 3, 2011 at 12:29 pm

I have a 15 x 30′ above ground vinyl liner pool. I have light calcium build-up along the water line and heavier build-up along the edges where the bottom and sides meet. Is there any kind of of scrub I can use to eliminate the calcium.? I heard someone mention epsom salts. Is it safe to use CLR or limeaway in the pool?
Thanks,
Karen

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fireyourpoolguy June 5, 2011 at 7:17 am

@ Todd,

The most effective solution is to have a glass bead or sand blasting treatment applied. This is something you can do yourself with the proper equipment, however, it’s a “skilled task”. Most companies charge around 3.50 to $4.00 per linear foot.

Terry

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James June 9, 2011 at 12:45 pm

I was told that an underwater acid wash may get calcium build up off walls of pool plaster. Will an under water acid wash work? Thank you for you help.

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fireyourpoolguy June 20, 2011 at 6:33 am

Hi James,

I haven’t seen/heard positive experiences about doing under water acid washes.

Terry

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Ben July 5, 2011 at 10:46 am

I have a three year old plaster in ground pool that has developed calcium deposits over the past 4 to 6 mos. It is getting worse and is only on the bottom surfaces, not the walls or tile. My pool tech has recommended an “acid bath” and he has also suggested “sanding” the calcium. He says the chemical readings are good and he is at a loss as to what is causing this. Are there any chemical treatments that will eat away at the calcium? Must I drain and acid wash?

Thanks

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cindy coniam July 24, 2011 at 2:05 pm

The front of my spa has glass block and the water flows over the block into the pool…the glass block has a calcium buildup…any ideas? I’m wondering if a pumice stone would scratch the glass?

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Jeri July 25, 2011 at 1:54 pm

I have a tumbled marble pool tile with calcium buildup. Will the muriatic acid damage the tumbled marble? If yes, then what can I do to remove?

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Anonymous September 21, 2011 at 2:26 pm

@Ben: Probably the use of hypochlorite is causing your pool floor to accumulate calcium deposits. Only thing you can do while it is filled is dive and scrub. Otherwise, do the easy thing and drain first before removal.

@cindy: It may scratch the glass so if you don’t want to possibly “repair” the glass, your best choice is to use glass beads blasting (yourself or hire someone).

@Jeri: Use of the acid solution with a brush should damage the marble. If you are really concerned, hire a glass bead blaster.

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Hal November 24, 2011 at 10:18 am

We have a very small pool (3500) gal and the tile around the top of the pool builds up with calcium. My water softener company is telling me to dump the water and refill with soft water. I’m willing to do this but would like to know if anyone has tried this.

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fireyourpoolguy December 21, 2011 at 6:54 am

@ Hal – that’s a pretty popular direction to go into and a good one. Soft water generally has substantially lower calcium/TDS counts than city/tap water.

Terry

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Glenn January 7, 2012 at 11:24 am

We have a 40,000 gallon Salt system Gunite pool with a large catch basin for the negative edge. The water source is a well and the water is very hard. There is some scaling on the main pool and I’m starting to see calcium at water level in the beach entry area. The big problem on the rock wall on the back side of the neg. Edge. There is a significant buildup on the flagstone. I’ve tried acid washing and scrubbing to a small extent and even pressure washing without much success. The Folks at Leslies aren’t giving me any recommendations and my pool builder is worthless. The pool is only six moths old and I am new to the pool ownership business. by the way the coping as well as the infinity wall are flagstone and I have moss rock planters. I’ve thought about replacing the rock with tile but I already have $70,000.00 in a brand new pool. I appreciate any suggestions.

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annie February 11, 2012 at 8:48 pm

I have a brand new pool ( plastered nov 2011) pool (no heater). We have noticed grayish discoloration after about a month and a half after it was filled. Plaster subcontractor has told us it’s the worst he’s seen and they have been in business since 1985. Pool contractor said it is caused by Calcium build up and would like to drain and acid wash it. He aslo said that if that does not fix the problem he will replaster without a charge. Do you guys think I should have them try without really knowing what caused the discoloration? I will have a lawyer draw a contract before they start draining pool tues. Thanks in advance!

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Deborah Read May 20, 2012 at 9:03 pm

Annie,
That sounds like a snow job to me. When we filled our pool up first time, we tried to move the hose around so the hard water didn’t stain the pool in one area. But it did anyway. It didn’t hurt anything and got lighter over the years. I’d get an opinion from a pool cleaning business that deals with chemicals, etc.

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Mike May 31, 2012 at 5:40 pm

I have a 2 yr old gunite pool / white plaster finish. Last season the pool surface was perfect at the time we closed it. After oppenning this season, there is a heavy scale that is on the walls and the bottom of the pool. The bottom of the pool scale is discolored somewhat (possibly from the heavy algea that was covering the scale. I have finally got to the point where the water is crystal clear, but the scale is rough to the touch and has bonded to the plaster so that I can’t scrape it off even if I use a puddy knife. I had the water tested and the TDS came in at 4000. The hardness came in at 400. There is also a thick white powdery substance in my cartridge filter. Sweeping the pool produces a white cloudy substance that puffs up from the surface when I hit it with the brush. Pool chemical sales guy says it is Calcium and I have put in a 6 quarts of scale inhibiter, 2 tubs of alkalinity since. Got it tested again today – alkalinity is good but hardness is still up at 350.

Could the source of calcium be coming from the plaster itself – possibly a chemical or something that is reacting with the plaster and causing the high Ca and the white powder-like substance that is clogging up my filter cartirdges?

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fireyourpoolguy June 7, 2012 at 1:59 pm

Hi Mike,

Good question – the likely scenario from elevated TDS and hardness is the water source itself. This will also naturally build up over the years too from adding normal chems, however, this isn’t likely taking place here since the water is only 2 years old. I would start by having the water source tested to see where it’s at coming out of the tap…if it’s well water, that would explain the likely source.

In the meantime, with the scale, a pumice stick is the way to go. A lot of work, but it’ll get the job done. If it’s in the budget, consider getting a glass bead tile clean done (generally around 3.50 per linear foot although this price will vary). It’s likely not only reducing the ability to filter water, but having a long term impact on the gunite as well.

Terry

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janet June 16, 2012 at 7:15 pm

how do I get the calcium build up off my MOSS rocks?

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fireyourpoolguy July 9, 2012 at 11:04 am

Hi Janet,

Couple of ways…

It’s lots of work, but one effective (and cheap) technique is to use a pumicestick. You can also use a glass bead tile clean – super effective, but typically runs around $3.75-4.50 per linear foot (with minimum).

Terry

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Mike H. July 14, 2012 at 11:12 am

Is it possible to remove calcium buildup from pebble tech (pool) surface without damaging/dis-coloring the surface? The hard water deposits have been an issue for several years. Mike H.

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fireyourpoolguy July 17, 2012 at 9:13 am

Hi Mike – I’d recommend looking into the “glass bead” method. I’ve been happy with this process over the yeas.

Terry

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dennis g July 22, 2012 at 6:14 pm

what grade of media should be used on pool tile?

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fireyourpoolguy July 26, 2012 at 10:23 am

#8 Dennis – they come in 50 lb bags for around $40.00/per.

Terry

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dennis g July 30, 2012 at 1:38 pm

glass or soda?

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fireyourpoolguy August 1, 2012 at 10:22 am

@ Dennis – Glass.

Terry

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David Norwood February 9, 2013 at 2:27 pm

I have a french grey plaster spa. 5 years ago I acid washed the spa and removed almost all of the calcium build up. It was a lot of work, but it was not perfect. Today, the calcium is back and 10x worse. I thought it might be a good idea to tile the entire spa. Can I tile over the existing plaster and calcium? Do I need to remove the calcium before tiling? What do you think about tiling to solve the problem or at lest make it easier to fix in 5 years from now?

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fireyourpoolguy February 20, 2013 at 10:25 am

@ David,

Not a good idea to tile over the existing plaster and calcium – likely to cause more issues as the pool continues to settle and it doesn’t address the root of the cause. The proper way to tackle this is to remove the calcium buildup and have the water tested for calcium and TDS. There’s likely elevated TDS levels in the water. If that’s the case, you’ll either want to replace all of the water or do an extended backwash several times to replace most or all of the water over a few days.

Also, make sure you’re staying on top of your pH and TA – this can slow down the process of calcium buildup.

Terry

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Keith March 5, 2013 at 9:35 pm

We have a gunnite pool with Slate tile at the water line. We had the entire pool redone in 2007 including new brick coping, slate tiles, and a full fresh plaster job. Before the end of the first season we noticed roughness on the new plaster. By the second year, my kids wore socks to swim and by year three we drained the pool and tried an acid wash. No luck as the calcium build up was too much for the acid wash to do anything. So, out came the power drill with a sander attachment and rough sandpaper discs. Took hundreds of hours (literally) but the job was fantastic… Fast forward three more years and we are facing the same problem… Not interested in sanding again.
We have been completely anal about our pH level and hardness… never out of whack.

Is there any chance this is a bad plaster job? And, what, other than sanding can be done to get my plaster smooth again?

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T. Duff March 27, 2013 at 1:27 pm

Hi Keith – if it happened that quickly, there’s a good chance the plaster job wasn’t done properly (didn’t cure long enough, inconsistent mix, too warm, etc). It’s tough to be definitive.

Without knowing all the details, my kneejerk would be that the plaster either wasn’t mixed enough or that a bonding coat/layer wasn’t applied.

For giggles, I would conduct another test for hardness (using a different retailer or testing kit) and also TDS.

Terry

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