High CH and scale

[Theresau]

There are ways to reduce CH without drain and re-fill. However it is a lot of work. Also a new pool will have a high CH due to plaster curing.

Found this forum. Thank you!!!

I plan to order test kit. Found it on Amazon. We are greatly suffering from what I assume is calcium scale. We have scale on the sides of the pool, in the DE filter and in the pool heater.

I just checked and it would cost close to $1,000 to replace our water. We need to find an alternative to stopping this scale problem. We didn't realize this was occurring right away. My husband took apart our pool heater when it started popping and yes it was clogged with scale...he removed that. Our DE filter is also getting scale clumps clinging to the DE. Yikes. We've never had this.

The output where the heated water comes through actually spits out little rocks at times that look like salt.

I think the issue occurred because we filled the pool about 5 inches or so with our well water when we started it up. We don't totally drain the pool in the winter nor do we cover it with hopes that snow/rain will help refill it and at times this has worked great. This year was a more mild winter so we had to add well water. Since then we've used our water softened water to keep it filled an inch or so at a time. We also have a portable RV water softener that we've used to fill an inch or so.

I've taken our water into the local pool store and no one has ever said we had too much calcium. Our water is beautifully shiny and clear. We are now having algae problems, something we've never had before and we've had the pool for 7 years.

My husband has had to clean out the filter practically every 2 weeks or less now. We may have to replace the inner filters because they have some scale in them.

It's an 18X38 above ground pool that's 4' deep. It's in a deck that's level with the ground at one end because we have a walk out yard so the pool is not a climb up even though it's considered above ground.

It's in sun all day. We like to keep it warm - we like 89.

I'm ordering the test kit overnight from Amazon and will do the test tomorrow.

We have a Nature2 Express plus we shock about every 5 days using Smart Shock. To clear up algae we've been using liquid chlorine but even 6 gallons did not work. Pool store advised using algaecide, 4 Smart Shocks, and muriatic acid to lower the PH. We tend to be high PH. It worked but within days came back. After reading this forum, I now think we have mustard algae so going to look into that as well.

Again thanks for this forum and any help on the calcium issue would be greatly appreciated. We don't have $1,000 to replace the water!!! Yikes.

 

[Foxy]

Re: High Calcium Hardness

Found this forum. Thank you!!!

I plan to order test kit. Found it on Amazon. We are greatly suffering from what I assume is calcium scale. We have scale on the sides of the pool, in the DE filter and in the pool heater.

I just checked and it would cost close to $1,000 to replace our water. We need to find an alternative to stopping this scale problem. We didn't realize this was occurring right away. My husband took apart our pool heater when it started popping and yes it was clogged with scale...he removed that. Our DE filter is also getting scale clumps clinging to the DE. Yikes. We've never had this.

The output where the heated water comes through actually spits out little rocks at times that look like salt.

I think the issue occurred because we filled the pool about 5 inches or so with our well water when we started it up. We don't totally drain the pool in the winter nor do we cover it with hopes that snow/rain will help refill it and at times this has worked great. This year was a more mild winter so we had to add well water. Since then we've used our water softened water to keep it filled an inch or so at a time. We also have a portable RV water softener that we've used to fill an inch or so.

I've taken our water into the local pool store and no one has ever said we had too much calcium. Our water is beautifully shiny and clear. We are now having algae problems, something we've never had before and we've had the pool for 7 years.

My husband has had to clean out the filter practically every 2 weeks or less now. We may have to replace the inner filters because they have some scale in them.

It's an 18X38 above ground pool that's 4' deep. It's in a deck that's level with the ground at one end because we have a walk out yard so the pool is not a climb up even though it's considered above ground.

It's in sun all day. We like to keep it warm - we like 89.

I'm ordering the test kit overnight from Amazon and will do the test tomorrow.

We have a Nature2 Express plus we shock about every 5 days using Smart Shock. To clear up algae we've been using liquid chlorine but even 6 gallons did not work. Pool store advised using algaecide, 4 Smart Shocks, and muriatic acid to lower the PH. We tend to be high PH. It worked but within days came back. After reading this forum, I now think we have mustard algae so going to look into that as well.

Again thanks for this forum and any help on the calcium issue would be greatly appreciated. We don't have $1,000 to replace the water!!! Yikes.

Welcome to the forum.
You have many of your own issues unrelated to this post, so you should start your own thread.

 

[Theresau]

Re: High Calcium Hardness

I'd like to start with the high calcium as I think it's the root of the problem. My husband greatly cleaned the filter and we're getting a better flow now. Algae getting better so I'm not worried about that.

Worried about the calcium scale - got the test kit today.

We recognize we will have to change the heat exchanger in the pool heater. It's definitely damaged. We didn't realize this was occurring until too late. Our water looks great.

We'll either change it or buy a new heater..

 

[Foxy]

Here's some info to get you started.
What we need to know to answer your questions
Pool School - Getting Started
Pool School - Solving Problems

The only way to lower calcium is to do a drain and refill, but you should probably figure out all of your problems first to create a treatment plan so you are wasting time and money.

 

[chiefwej]

All that Smart Shock is dichlor which will be driving the CYA higher and higher. You don't say what you are using for your daily chlorine demand. If that is trichlor pucks, we may have identified why you are having problems with algae. That combination will make the CYA level so high that it's difficult or even impossible to manage. High Calcium levels with careful testing and management can be successfully dealt with up to around 1000 CH. Above there it becomes too much of a tight rope act.

Without any test results about the only advice I can offer is to make sure the test kit you get is one of the two that we recommend. Taylor K2006C (the C is important) or TFtestkit TF-100.. The T-100 is the better buy as it contains more of the tests you will do the most. While waiting for your test kit you can begin studying Pool School. That's the button at the upper right of this page.

Once you have some test results we will be able to begin advising you on how to make your pool a Trouble Free Pool. Welcome, there are lots of pool experts here who are happy to help you solve any problems and answer any questions.

BTW: Many, many years ago, I used to live on Woodland Lake in Brighton.

 

[domct203]

........I'm ordering the test kit overnight from Amazon and will do the test tomorrow........

Please post your test results, the longer you wait the worse it may get.

Please list:
FC
CC
pH
TA
CH
CYA

 

[Theresau]

I purchased the Taylor T-2006 kit. First time I've used it .

FC 4.0
CC 1.5
pH 8.0 (5 drops brought it down to 7.4)
TA 160
CH 300
CYA 80

This was after shocking with 4 lbs. of Smart Shock about 40 hours ago or so. (My husband brushed the sides of the pool right before and algae did turn grey over night.) We swam in it last evening. Our normal would have been 2 lbs.

In regard to what we do in between - just the Nature2 Express cartridge - no chlorine except at shock time. This has worked great for us in the past. Nature2 Express Mineral Sanitizer.

Our pool water is always beautiful - it shines. However, the pool store does not check for calcium hardness, just total hardness and ours is on the higher end but always within their parameters.

I did read in the Taylor manual that the CYA could get high from the smart shock.

Typically we only use the Smart Shock as a weekly shock treatment and we were only putting in 1 lb. when we got the algae. When we fight algae, we usually do this with liquid chlorine. (We should have been using 2 lbs. of Smart Shock.....) Pool store has always told us not to use liquid chlorine for weekly shock as the sun dissipates it too easily.

However, about 12 days ago, the pool store said to do the 4lbs. for the algae - so we just did that again Tuesday as the algae came back. (Very expensive ) Our PH was 8.2 then so they had us add .5 gallon of muriatic acid.

I'm so glad we found this site - it's led to our doing much more research. For example, the other granular shock that the store carries and is the one they recommend is called Burnout - it's the calcium chlorine. We did use that one year and we had a great deal of scale on the walls of the pool - worse we've ever had. We drained the pool very far down that winter. It was a big snow winter so it filled pretty naturally as we don't cover it.

Pool is 18x38 above ground with deck surrounding - basically at ground level at one end. We have a double deck. It is in sun all day. We tend to keep it warm when we use it. At least 88. If weather is not good, we don't heat it. Once it turns around, we will run the heater all evening until the next day.

We have a Raypak NG 200k pool heater and a DE Doughboy filter.

Any help will be appreciated. As I said earlier, we recognize we will have to change the heat exchanger...this is available. I'm sure we won't drain and refill the water as our time left for swimming is probably only 3 weeks. Once September hits, it's a rare day that we can swim...just gets too cold here.

P.S. Studying PH and alkalinity - your site is just great. Noted that Pool Math said to lower to 7.2 to lower alkalinity and then aerate to raise the PH back up. So I began to study what it meant to aerate the pool. I would say both of our returns aerate - especially the one closest to the pump. It's like a mini waterfall - it's above the water - it shoots up and then falls down. The one at the other end of the pool is the same design but has less pressure - it is the heated water. The heater is about 30 feet away from the pump and filter.

If this is the case, could our main return be part of the cause of our PH problem?

 

[kabutotx]

Yep. Plugging into PoolMath you get a .76 CSI, you want to be around 0. You need to use Muriatic Acid to get your pH down to 7.2. Also your TA is high so read how-to-lower-lowering-total-alkalinity

You need to eventually drain some to get your CYA down. The Smart Shock adds CYA which makes your chlorine less effective at high levels. Smart Shock also says it has copper. Just use liquid chlorine or bleach. Same thing but the pool chlorine is usually stronger.

 

[chiefwej]

And that Nature2 system does not sanitize anything. It is a mineral system that adds metals to your pool water. Those metals may do a little for algae, but they can also cause more problems than they do good. Even their own literature says that it "reduces the amount of chlorine needed", not eliminates it,(which we would even dispute). Chlorine is what sanitizes a pool. Keep a pool properly sanitized and you never have to worry about algae. So, there is no need for troublesome metals in your water.

Your problems stem from:
1. too much CYA, from all that powdered shock you have used
2. No chlorine, since you aren't meeting the daily chlorine demand by regularly chlorinating the pool
3. high calcium
4. High pH (from constant aeration which causes the pH to consistently rise)
5. Dependence of a mineral system that will only cause problems

If you are ready to learn a better way of pool care there are lots of folks here that will be glad to help. You have so many issues that a drain and start over may be the best option. Draining is the way to get rid of CYA, metals, calcium all at once. Without knowing your pool capacity and guessing around 20k, I find it hard to believe that, I living in the middle of a desert, can fill my pool for less than $100, while you living in the middle of the largest fresh water supply on earth, will pay $1,000 for a similar size. Is water really that much more expensive in Michigan than Arizona?

You need to create a signature that includes all the info about your pool (see mine and others). This helps us in guiding you without having to ask questions over and over

The test kit you bought has all the test you will need, but if you bought the K-2006 instead of the K-2006C, the reagents are in very small containers and you will run out quickly.

 

[Theresau]

This has been a great resource already. Thank you for your replies.

1. My husband is already looking into changing the output so that it's not aerating as it is. Those were our thoughts too that this constant aeration may be the culprit of our having too high of PH. (I like hearing the sound of it though and will miss it ). The pool was in when we bought the house so we had no idea this was an issue. He's already checked into how to change this. We'll let it aerate through the night tonight since we're trying to get the PH down to lower the alkalinity.

2. Yes we now know the Smart Shock wasn't such a great idea and it was expensive too. So we're going to go to liquid chlorine or bleach. I have to admit here that my husband had suggested doing this not because it was better but because of the expense - so he got to be right on this one . But the pool store was adamant it was not a good thing to do - that it was a waste of money to use it.

3. The high CYA and high calcium will have to wait until next spring when we open the pool again. In fact, we are considering changing the liner as this is it's 9th season so it will require a full drain to do that. Yes, it's $404 for 9,000 gallons of water here. I was shocked when I heard that price. And it worries me because it's city water and what will that have in it.........this is not Detroit water but a small municipality's water so we have to think this one through. It's way too much for us to fill ourselves as we have a well.

4. We put a full gallon of muriatic acid in the pool as the PoolMath suggested. We're running the pool all night as well (pool heater disconnected and turned off). I'll recheck the PH in the morning.

5. The high calcium is probably from our well water - we filled the pool with well water when we opened it. Come October or so, we'll drain down about .5 of the water to prep for winter. If we don't get a new liner next spring, we will top off the pool when opening it by purchasing water. We usually have to top off about 4" in the spring (we get that much snow and rain in early spring to fill about 18" or more). After that we'll use our softened water which we've done for the rest of the fills this summer. This drain down should help with the CYA too.

I can't tell you how disappointed I am in our pool store that they advised us to use 4 lbs. of the Smart Shock rather than liquid chlorine - they had to know that this would cause our CYA to go up and that it would be permanent. I plan to call them. We had no idea about this.

I'm also disappointed in them that they have always suggested we use the granular Burnout which is calcium chloride. It's a vinyl pool and per their tests for years now our hardness was always on the higher end so our calcium had to be on the high end...they should have know we shouldn't add more calcium.

Yep I wish I'd bought the K-2006C but we're nearing the end of the season. I acted too soon.

This has been a lot of "you don't know what you don't know".... We're DIY's in regard to any maintenance around the house, cars, etc. - but this has had an expensive result because the heat exchanger is definitely toast and some of the filter elements are looking pretty filled with calcium that is not getting removed by just spraying it off when my husband takes apart the filter. This was a very hidden issue as our water looks and feels wonderful close to 100% of the time. It sparkles. And when we would get it checked we would usually be told it was in great shape. Occasionally the PH would be too high and we would add acid as they directed. But there was definitely a problem considering the scaling that occurred in the heater and how it destroyed the heat exchanger. And this is evidently not a new issue but an ongoing issue considering the amount of damage.

Soooo glad to have found this forum.

 

[chiefwej]

A CH of 300 in NOT what caused the scale. I have successfully managed my pool (with no scale) at CH levels above 1,000. What does cause scale is allowing the pH to be too high, for too long. The predictor of scale is the CSI being at or above +.60. The factor in CSI, over which you have the most control is pH. If you allow the pH to be at or above 8.0 you are very likely to have scaling.

The two things that you always want to carefully monitor and control are FC (Free Chlorine) and pH. It would appear that not controlling those two are also the source of most of your problems.

 

[Theresau]

Thank you. We'll monitor both more carefully especially now that we have the test kit.

 

[Theresau]

This morning's results after dumping in a gallon of muriatic acid last evening and running pool all evening: PH 7.4 and Alkaline 120.

I also rechecked chlorine because I did the test yesterday incorrectly - did dippers wrong (I won't admit how I did it wrong - I'm a computer tech!!!). FC 7.5 and CC 0. FYI we haven't added any chlorine since Tuesday around 6pm EDT.

I now found your instructions on doing the tests - especially the one for CYA and our CYA is not 80 but 50.

CH is 250.

Getting there.

Thanks for this forum again.

 

[chiefwej]

With a CYA of 50 and CH at 250, no draining should be be needed. Those levels are well within managable limits. You need to use PoolMath to dose the pool with liquid chlorine (AKA bleach). Your FC target should be 6-8 and you must never let it drop below 4. You can also use Pool Math to calculate CSI, but with a vinyl liner you are only really concerned about high CSI, anything above +0.30 is a problem. As a general rule, if you keep the pH in the 7s, you at least won't be adding to the scale. Allow it to get to 8.0 or above and you are building even more scale. Considering how low your CH actually is, the amount of scale you are describing is indicatitive of failure to manage high pH levels over a prolonged period of time.

 

[RadEngr70]

With a CYA of 50 and CH at 250, no draining should be be needed.

Totally agree with chief. Those numbers are fine. Test your FC/CC and pH daily... adjust your pH as necessary (and it will be frequent to begin with until your TA lowers), and your TA will fall in step. Keep your CSI in the -0.6 to 0 range, as this can actually reverse the scaling in the long term. (always keep your pH above 7.2 though, for swimmer comfort and the health of your heater).

Good luck, think you're doing everything right so far.

 

[Theresau]

Thank you again.

Yes I'll keep checking FC, CC and PH daily. My guess is PH will go up again. We think it is the constant aeration at both ends of the pool. We had no idea this was an issue. It would mean draining the pool down to fix it so we'll just limp around the next few weeks. Husband is cleaning the heater's heat exchanger again today.

He plans to fix the aeration including putting in a valve to the return that is nearest to the pump so that the output is less there and more is carried to the pool heater. He also plans to replace heat exchanger and some of the filter screens in the filter. Problem is the pool liner still has scale on it...winter may remove some of that it's done that in the past. We don't want to replace anything until we get this under control - including a new liner. This has been an expensive lesson.

We feel really dumb about the aeration - we would never have thought of that without this forum pointing out that aeration can be used to raise PH.

(I'll miss hearing the waterfall - I can hear it all the way to the house...it is also probably causing the pool to lose some water as well...)

Thanks again.

 

[RadEngr70]

I think if you get your TA lower, 60-80 ppm, you may find that rising pH won't be as big an issue, and you'll be able to enjoy your waterfall again...

 

[Theresau]

I'll work on that too. Today it is PH 7.6 and FC 6.5 and CC 0. We added some muriatic acid enough to bring back to 7.4 and after a time we added 3.5 gallons 12.5% to do a mustard algae shock - still seeing "some" yellow green algae around like on the ladder.

Now we're looking into how to adjust the flow direction. We have two of the Pentair 600040 Aqualuminators - one at each end of the pool. Not sure why the previous owners put these in. We've never plugged them in - never worried about lighting up the pool as it's in full sun. And we would never swim at night, too many mosquitoes!

Studied up on Nature2 Express and yes they have backed off their claim that this can replace chlorine - now they state that it helps the water glisten which ours does. At first they stated it could but you would need to "shock" once a week (which was basically adding chlorine not shocking per se).

We will be removing that when we winterize.

 

[mknauss]

If you have algae you need to SLAM. It is highly unusual to have mustard algae, and the protocol for it is the same, a SLAM. IF, it really is mustard algae, then after meeting the SLAM criteria to completion you raise your FC for 24 hours to mustard algae levels.

Pool School - Mustard Algae

Hope that helps -- take care.

 

[Theresau]

Thanks.

Ok I did read that on the forum first. But I'm not doing two steps so here's hoping we'll be ok. I just went to the mustard algae level of FC and used the Pool Math to determine how much chlorine. It's going to be a couple of cool days here so we'll miss those days swimming. (We only have so many days left here in MI.)

I feel sure it is the mustard algae - it's acted like it and looks like it from all I've read here and elsewhere. We've had the other algae before and quite different than this.

We are studying our lights and flow director and it turns out we should have been able to turn it but we can't. Previous owners put it on too tight so we have to wait until we bring the water down.