Calcium Levels

[modog]

I am in Dallas, TX and we have hard water. My calcium is a bit over 400 right now. The pool is around 2 years old. I do get deposites on my waterfall and on the tile splash. A) is this level dangerous to my equipment/pipes/etc B) How to get rid of the deposits C) How to decrease the Calcium levels?

Thanks for the help!
Mo

 

[Bama Rambler]

There are only two ways to lower CH (calcium hardness). Either replace water with lower CH fill water or have your water ran through a reverse osmosis filter unit.

What is the CH of your fill water?

A CH of 400 is high but not unmanageable. Post a full set of numbers and we can advise you about where your numbers should be to manage it. The trick is to use Pool Calculator and keep your CSI negative.

 

[257WbyMag]

Do your deposits look like these on my tile and between my waterfall rocks?

If it does, than it is probably efflorescence, rather than scaling. If the scaling wholly surrounds your pool and is on all the tile, it's a calcium issue.

 

[PaulR]

Anyplace where water gets splashed, and then dries, is likely to show some deposits. If you see it happening someplace that's always under water, then it would be scale.
--paulr

 

[modog]

Then it would be scaling. It is building up where my waterfall comes down from the hot tub into the pool. Any recommendations on how to get rid of this? I also get some temporary white stuff on my stone that doesn't even touch water. What is this? Unbalanced water causing this?

I also have 2 scuppers that aerate with the waterfall so I was told my TA will drop quicker. Is this true? I am also always fighting to keep my ph under 7.6.

I am trying to stabilze to prepare for borates. At the same time I had some concerns. Here are my results you requested. I just added 175oz of bleach and 24oz of MA after running these tests.

1) Is there such as thing as too low CYA? I redid the test and get somewhere between 25-30. Always second guess myself on when that dot disappears
2) Any recommendation on how to get my CH lower. You mentioned the CSI index needs to be negative. Can you please provide some more detail on this meaurement?

FC = 1.0
CC = 0.0
PH = 7.8
TA = 90
CYA = 25
CH = 410

Your help would be appreciated. I am a true BBB believer now and no more pool store bought chemicals!

 

[JasonLion]

1) Yes, CYA can be too low in an outdoor pool. Your is marginal, you should bring it up, but it isn't dangerously low.
2) CH at 410 isn't too bad. It can easily be managed by lowering your TA level just a little. It is actually a good idea to lower your TA down to between 60 and 70 anyway to reduce the amount of PH drift.

CSI is something that is calculated using the numbers you just posted and the water temperature. You can use the Pool Calculator, see the link in my signature, to do the calculation for you.

Stone work above the waterline will always get some calcium/salt deposits on it from water that splashes onto the stone and then evaporates. You can minimize the amount of such deposits by keeping the CSI slightly negative, but you can't eliminate them completely.

Stone work below the waterline will be completely protected from future deposits as long as you keep your CSI slightly negative.

 

[modog]

How do I increase CYA? Is there an acid I can buy to do this? What level would you recommend?

I usually keep my TA at 90. I will decrease it to the 60-70 range. With my CH being at 410, what is a dangerous number? Any other way to bring it down?

So how do I remove the scaling?

Thanks.

Mo

 

[257WbyMag]

Anyplace where water gets splashed, and then dries, is likely to show some deposits. If you see it happening someplace that's always under water, then it would be scale.
--paulr

True to a point. Yes it is scaling, but not from the same source. Scaling on your plaster (always underwater) results from having high calcium levels in the water. The calcium is deposited from the water itself. Efflorescence results from minerals leaching out from the mortar between the rocks on coping when exposed to any moisture. The source of the minerals in efflorescence is the mortar, not the water. This can occur whether your pool water CH is high or not as it is a separate type of problem.

The photo above is my own pool. The scale, as we are calling it, originates from the mortar. It can be removed with a little muriatic acid that had been diluted with water (like 1 part MA and 10 parts water) and brushed gently with a stiff brush. Don't use a metal brush. Use care here though because it is easy to remove more than just the scaling. Rinse the area well with water after you are finished.

Your CH isn't too bad and you CSI is not beyond 0.6 yet. If you keep tighter control of your pH, say around 7.3, you'll be doing great.

 

[Butterfly]

How do I increase CYA? Is there an acid I can buy to do this? What level would you recommend?

You increase your CYA by adding CYA (cyanuric acid), also known as Conditioner or Stabilizer. Look for 100% cyanuric acid (ingredients) or close to 100%. Wallyworld has been touted to have some good CYA in that it is more powdery and dissolves faster, and is also a good price.

Recommended CYA levels are 30 to 50 for non-SWG pools. Since you are in Texas, I suggest a CYA of 50-ish.

 

[modog]

Thanks for all the info. I will look for the CYA acid. Is there a post on how much to add per 10k gallon? Also, is it added to the deeper end, return flow, skimmer?

Regarding the scaling, it is on the mortar and tile backsplash at the water line just under the waterfall. I have tried the MA/Water combo with brushing and not much luck. I will keep at it.

Thanks again for your help!

Mo

 

[257WbyMag]

CYA is sold as stabilizer. You're going to have to look at the ingredients on the container. What you want is as close to 100% cyanuric acid as you can get.

Use the pool calculator (link in my signature line) to determine how much to add to your pool If your current CYA is 25, you would want to bring it up to 40. Plug the number of gallons in your pool into the "gallons" field at the top of the calculator page, then scroll down to find the CYA section. Put 25 in the left box and 40 in the right box. That you tell you how much to add.

To add CYA, you can simply put some in a sock and hang it in front of a return. You can also put it in your skimmer. If you put it in your skimmer, you don't want to backwash for a few days or you'll lose it. CYA can take up to a week to dissolve. Don't recheck for CYA for at least a week after adding it.

You may just have to gently scrape at the scale. Mine comes back every year in that same spot and just yesterday, I removed it for the season. I brushed it with the MA and water solution, rinsed it well, and then got in there with a little putty knife to scrape what was left from the rock and tile. After the MA/water treatment, it gets pretty soft and so is easier to remove at that point. Just be careful. You don't want to remove more than you bargained for.

 

[cheddar85]

The CYA at Walmart is 94%, but it's what I've always used and it works fine.

Butterfly is correct about it being more powdery, and from my experience it does dissolve quite a bit faster.

 

[geekgranny]

I started helping my Dallas friend with her pool a couple of weeks ago. Her CH was 700 but her TA was very low. I don't have the numbers in front of me but I think it was around 40, which is where we left it. pH remained around 7.5. After I got CYA added and doing my final tests before being away from the pool for a few days her CSI was -0.2. Not bad with such a high CH level. Most of her calcium came from her pool guy using CalChlor, for over a year, the only sanitizer he used. Of course she had constant algae and 0.0 CYA. I've had her pour bleach in every couple of days. Her pool guy was there yesterday and said the water is perfect. (He probably only tested pH and Cl.) All he had to do was empty the skimmer baskets. I told her, weeks ago, to not let him do any brushing or add anything. If you brush to the bottom drain it all comes back out the returns.

Her pool is beautiful now, even though her filter spews out any DE added to it so we have been running the filter without adding any DE. The Aquabot is slowly capturing the massive amounts of DE that settled on the bottom of pool. I've left instructions that no one is to brush the pool until I get over there to check out the filter today and get a resolution to filter problem. BTW... I've recommended a sand filter and explained why; lower up front cost, very low maintenance, so that she will be able to backwash even though she is disabled. She doesn't have loads of fine dust like I do; mostly Juniper "needles".

gg=alice

gg=alice

 

[geekgranny]

The CYA at Walmart is 94%, but it's what I've always used and it works fine.

Butterfly is correct about it being more powdery, and from my experience it does dissolve quite a bit faster.

I've used several kinds and prefer the Walmart the best. I had to add two lbs yesterday. Put in a knee high, suspended it in front of strong return (as it leaves the stocking, yes, in a very fine powder, you'll probably have to reposition it some). In three hours it was almost totally out of the stocking. I massaged the last bit for a minute and totally emptied the stocking.

I keep a special rock for adding CYA. Just tie a string to the stocking and wrap it around the rock. When not in use the rock is decorative. It's not too heavy but heavy enough (probably weighs what about three or four bricks weigh) to keep the dogs from knocking it into the pool.

gg=alice

 

[geekgranny]

As the CYA test is so subjective, it would be best to put about 2/3 to 3/4 of the amount called for for the first does. When I test for CYA, especially when the ppm is a low number, it is easy to put too much in. And for some reason I've always gotten to my correct number range adding a little less than the calculator calls for, when I use the Walmart CYA. I have found that I can get a reading faster using it. It seems to dissolve into the water better and faster than others I've used.

gg=alice

 

[modog]

Wow, thanks everyone for the replies. I will go find this "stabilizer" CYA and add it to the pool. I will then bring my CYA up to 40. I will keep working at the scaling and see if I can get it off.

2 last questions....for now
1) If I am able to keep my ph around 7.3 and my TA at 60-70 all summer, will this reduce my CH from 410? Or is the damage done and that is the lowest it will be?

2) I just had a very dim light bulb go off in my head based off your brushing comment. Every week for 2 years I have been brushing my pool steps and walls and most of the floor. My pool sweep runs 2 hours a day and seems to do a good job of sucking up the dirt. I assume the rest gets sucked into the main drain and into my DE filter. Is this accurate? It doesn't get recycled back into the pool?

 

[JasonLion]

1) No. CH can only be changed by either adding calcium, replacing water, or a reverse osmosis treatment. Those steps will slow down or eliminate future problems, but they won't clean up already existing problems.
2) Yes.

 

[modog]

If I add more water from the tap, I assume I need to check the CH levels. If it is high, what are my optoins? You mentioned reverse osmosis. What is that?

 

[JasonLion]

Reverse osmosis (RO) is a filter process that removes most of the dissolved chemicals in the water, lowering TA, CH, CYA, salt, and just about everything else. The equipment is large and expensive, so you normally hire a service company to come over and process the water through the equipment on their truck/van.

Your levels aren't anywhere near high enough to justify an RO treatment.

CH levels up as high as 1,200 can be managed by lowering PH and TA and monitoring them to make sure they don't go up. With CH levels around 400 to 600 this is quite easy to do. As CH levels climb it becomes progressively more difficult.

 

[257WbyMag]

I don't believe that there are any RO services here in the DFW metroplex. Of course, we don't have the CH issues that AZ has either.