order of events while replacing water due to high calcium hardness

Sandi DC

Bronze Supporter
Dec 16, 2019
40
South TX
My readings from this morning were as follows:

FC 2.6
CC 0
PH 7.8
TA 80
CH (honestly unsure Last test was 600 early in the week....see below)
CYA 50
TEMP 78
CSI .38

Our pebble pool was just installed last October. I thought that I was maintaining it properly by checking the chemicals every week and putting the chlorine and PH back in line once per week. Recently I noticed bright white, very small smooth spots appearing in the pool and at first was inclined to think that it was just part of the pebble aggregate being exposed... still curing? as I have read that the curing process can take up to a whole year. Our calcium hardness of the water out of the spigot was only 150 when I had it tested back in October. I take water in to Leslies monthly, as per the plaster warranty instructions and saw that the number increased each month. I read that I should keep the PH on the low end near 7.2 to keep scale from forming once the calcium hardness level had gone over 400 (a few months back it had reached that point). My last leslies test was 3/5 and it was at a 600 (597 to be exact). Again, I was WEEKLY (as per what I thought was correct) adding MA to bring the PH back down..every week it would climb to around 8 (I was also using test strips because I was intimidated by the Taylor Kit that my husband bought and asked me to learn how to use...sigh...I know, I know :). A neighbor was over a few nights ago and told me about the CSI reading and told me to get straight and learn the Taylor kit. I did and am now comfortable using it and have been testing daily. He thinks the white spots may be calcium deposits. Today, my husband cleaned the cartridge filters and we started replacing the water by filling while simultaneously removing water through a hose hooked up to the pump leading out into the yard. After 5 hours of this, our CH is only down to 570. In the meantime, I see the water turning green from the water being put into the pool. At this point I am wondering if I need to be testing and adding chemicals for the chlorine and ph as this process seems as though it will take a long time. Thoughts? recommended order of events? Any idea why my calcium hardness got so high? I have been using liquid chlorine and 31.5 20 bromine muratic acid. So sorry if I have provided way too much info. but I am so ridiculously new to this and feel clueless. Oh.... lastly... once the water line had receded, we did notice a faint smooth white chalky line on the tile. You can't see it unless the tile is dry (sand colored tile).
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
Welcome fellow Texan! :wave: Well, let's cover a few things in your post:
1 - Never trust pool store testing. It's good you are finally testing on your own. Stick with it.
2 - CH only goes up from fill water being hard or adding it via pool powders (i.e. Cal-Hypo). If you used any Leslie's shock bags with cal-hypo, that would do it. If not, your fill water may be harder than you think.
3 - What part of S. TX are you at? S.A, Corpus, etc? It helps to give us a better picture.
4 - A CH of 500-600 is a bit elevated, but not unmanageable. If you are really firm on lowering the CH more, make sure the fill water is only 150 (CH) or you'll just be adding hard water on top of hard water. You might consider staying where you're at and waiting for the next few storm systems to come in and use fresh rain water to help. As long as you are only using liquid chlorine, the CH will not increase except for the house water.
5 - See if you can scrape a bit of that white stuff off. Confirm it's calcium by placing on the grass in a pile and pouring some acid on it. If it fizzles, it's calcium. It would be good to confirm.
6 - Green water is never good (algae). Our temps are increasing and your FC is way too low for your current CYA of 50 (see FC/CYA Chart). Green means algae, and algae means time for a SLAM Process.

So a lot of info to process. Basically, I would consider stopping the water exchange unless you really want that CH lower. Once the exchange has stopped, begin the SLAM Process by doing a pre-SLAM lowering of the pH to about 7.2, then taking your FC up to "20" and keeping it there until you pass all 3 SLAM criteria. Hopefully you'll have a short SLAM by catching it early.

As for the suspected calcium, focus on using rain water or adding soft water if you have that ability at home. I like to lower the pool water level just before a big storm to take full advantage of fresh/soft water. You can use the PoolMath tool (or APP) to try and keep your CSI slightly lower for a while (-0.1 to -0.3) and that may help with consistent brushing. Time will tell. But with a new pool and all, I would be careful about forcing the pH really low for a long time as you don't want to mess-up any other plaster with water that's too aggressive. At this point, let's get the water clear & clear again with no green. You can always address the calcium later.
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
19,678
Northern NJ
Welcome.

Right now your CH level is not your major problem. A CH is manageable and we can help you with that later. Right now your FC is within the level where you can get algae. You mention green water which may be algae starting to form. Let's deal with that fist before it becomes a green swamp.

You need to raise your FC up to at least 6-8. See FC/CYA Chart

Please so an Overnight Chlorine Loss Test and determine is you need to do the SLAM Process to kill any algae.

Once you have a good FC level with algae free pool then we will discuss your CH level and the white spots.
 

Sandi DC

Bronze Supporter
Dec 16, 2019
40
South TX
Thanks y'all!

I was not clear in mentioning that the water was crystal clear this morning before we decided to do the water exchange. The green water is coming straight from the spigot while filling. Can that be algae water coming right out of the spigot?? My husband noticed it was green as he was filling the pump to prime it. We went out for the evening and the pool is now full again. I will balance ph and chlorine in the am. I presume this time of year, I will need to be out there balancing chemicals every day?

We are in Poteet, TX, approx 25 miles south of San Antonio. Since having the pool built in October, we have only run approx 6 chlorine tablets through the dispenser and only used powdered shock 1 time. Since then we have been using only liquid chlorine and MA on a weekly basis. I do add 2.25 oz of Polysheen Blue each week and starting last month we have been adding 6oz per month of beautec scale prevention as per recommendation by our pool school person upon startup. We never buy products from Leslies :).

There is not enough of any kind of buildup to scrape anything off of. It all feels smooth. Does that mean it is not calcium? or possibly just in the very early stages of build up? We do have a water softener in our home, but the spigot that we fill the pool with bypasses the system. I will see if my husband will consider replacing water with softened water if that would be helpful!

I am very grateful for the detailed help. Thank you!
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
Poteet,.... Strawberry festival capital of the world, or at least Texas. :) Are you on a well? I'd be curious about the green water from a spigot. A couple other things .... the tabs .... you gotta pull them out. Check the container. They either have Dichlor, Trichlor, or something else listed as an ingredient besides chlorine. Let us know, but either way it's not good for you. Your CYA and CH are both high enough. Use just liquid chlorine or regular bleach each day. That's it. Also, that BLUE stuff, .... no more. Probably adding copper to your water which is never good. Just pool industry junk.

Get that FC increased and consider doing that Overnight Chlorine Loss Test so we can rule-out algae. We'll start fresh again tomorrow. :) Nice to have you in the forum.
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
19,678
Northern NJ
What is the source of your fill water? The fill water being green is not from algae. Pool water changes color with chlorine and the other chemicals that bring pool water into balance.

Here is a typical Basic Pool Care Schedule - Trouble Free Pool

Let your new water circulate for 24 hours, add chlorine to it, and then post a full set of test results.
 

Sandi DC

Bronze Supporter
Dec 16, 2019
40
South TX
ackkk.. I I did not see the instructions sent at 9:28 by ajw22 ( I have email notifications turned on..sigh..but I did not get it. I am just now seeing that mssg, after tending to the pool all day. Our water is city water that is notorious for being orange (not green..I don't know what my husband saw yesterday). I will start with my test results of the water from the hose that was filling the pool yesterday which is directly connected to the same water line that my husband used out at the pump when he filled it to reprime after cleaning the cartridge filters.

OUT OF HOSE results this morning:
FC 0
PH-was yellow (not orange..not green) I am presuming this meant less than the lowest 7.0 test level
ALK 110
CH 140
CYA - UNDETECTABLE...filled the entire container and could clearly still see black dot

Not sure if or why it would matter but.... the spigot results were different from Leslies back in October, when our pool was finished being built and we had it tested. Those results were:

FC 1
CC 1
PH 7.6
ALK 120
CH 150
CYA 20

I will now put readings from this morning prior to adding any chemicals. (In parentheses are yesterday mornings readings prior to us deciding to replace water due to the high CH number) I can't say exactly how much of the water we replaced since we were doing it simultaneously but I find it very interesting that the CH decreased a bit, but not the CYA?

FC 2.0. (2.6)
CC 0. (0)
PH 7.9 also interesting if there is less than 7.0 in the spigot water? (7.8)
TA 90 (80)
CH 510. (597)
CYA 50. (50)
TEMP 76 (78)
CSI .46 (.38)

greenish water this morning. yesterday was crystal clear

TODAY I DID: 9:22am
1. add muratic acid as per pool math to lower to ph of 7.2
**note... I forgot to retest to make sure that worked properly, however, since using my taylor test kit, the ph math and results have been spot on when I test later in the day to see if the amt I added worked...eeesh, I hope I haven't messed anything up.

2. 9:47am added 253 oz of 10% bleach as per pool math
3. 1:07pm FC 16.2 (in the last day or 2 I have read how to "date" the chlorine...the jugs I was using said 19 250. Is there math to compensate for older chlorine? are there guidelines as to what is too old to buy or when it is just better to buy the 6%?
4. 1:14pm. added another 53 oz 10% bleach as per pool math...still trying to reach 20
5. 4:25 pm FC 17.8
6. 4:30PM added another 36oz 10% chlorine (bought today with a 20 045 code
brushed tanning deck and walls
*water seems less green to me*

when we started adding chemicals we turned the pump on high (3150) and intend to leave it run all night. Is this correct?
what else do I need to know today?

Gosh y'all.... I can't thank you enough for reading all of this and helping me make sense of it! I will be thrilled to be able to help someone else one day.

Texas Splash... yes sir! We lived in San Antonio for over 30 years and finally got us a small place in the country right up the road from the festival grounds! It is just 2 weeks away. Not sure if they will cancel or not this year. Prayers for the world right now...wisdom, faith and peace. <3
 
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Texas Splash

Mod Squad
TFP Expert
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Our water is city water that is notorious for being orange
Sounds like you may have some iron in the water - maybe. Take a look at your old Leslie's printouts if you have them and look to see if there was any iron content noted. Or, it may just be sediment. We'll come back to that later.
For now, stick with the SLAM. No need to run the pump so high though. An rpm of about 1200-1300 will do just fine just to keep things circulating. Your CH of about 500 is fine as well. I wouldn't sweat trying to lower it much more.

Now once the SLAM is over (passed all 3 criteria), watch that pH and try not to let it get over 7.8 for two reason - your CH (scale) and potential iron int he water. Also, watch the water for any color changes or small stains as you SLAM which is another indication of an elevated iron content in teh water. Maybe the orange is just sediment, but we'll see. If you have any question about the SLAM, let us know.

Oh, about the chlorine. Yes, it losses a little strength each month, but fortunately the 2019 batch you got was still in cool weather, so not the worst like summer bleach. :)
 
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Sandi DC

Bronze Supporter
Dec 16, 2019
40
South TX
Original test result from spigot done at Leslies shows no iron, no copper. Every monthly test since shows the same, except the 5/3/20 which shows .1 for both.

ugh! I just checked the chlorine and it has dropped down to 16 since the last reading. Does that seem odd? Adding more chlorine now.
 

Texas Splash

Mod Squad
TFP Expert
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I just checked the chlorine and it has dropped down to 16 since the last reading. Does that seem odd?
Not really. FC normally drops a bit, and with algae will drop a little faster It's good you are checking often. As for the metal levels, we'll leave it alone for now unless something obvious brings us back to it later. SLAM away!
 
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Sandi DC

Bronze Supporter
Dec 16, 2019
40
South TX
at 7pm I told you my FC had dropped to 16. I added 56oz of LQ and at 8pm it was 18 soooo.... my common sense told me that my bleach wasn't a true 10% as I wasn't able to get it up to 20 all day sooo... since it raised by 2ppm by adding 56oz, I added 56 more ounces to raise it the remaining 2ppm to equal 20. Next hiccup... I am quickly running out of R0871 drops and just realized that I have been using the 25ml mark and could have been using the 10ml mark saving LOTS of drops. eeesh! Is there a difference to y'all in which mark you use to test? Here is why I am asking. I just tested using the 10ml mark and came up with a FC OF 27.5. yikes! Please tell me that I am not hurting my pool! I also don't think that I have enough drops to test anymore. I am hoping that a neighbor might have some that I can borrow in the morning. When I drew the bottle of water out of the pool the last time, it looked really clear to me! (hoping it looks the same in the daylight tomorrow.)
 

Rancho Cost-a-Lotta

Silver Supporter
Apr 10, 2018
1,598
Rancho Cucamonga, CA
I'll chime in since I'm on the west coast and still awake. Don't worry about the elevated FC level. It won't hurt anything. Your priority is getting yourself some R-0871. Around here it's hard to find, but some pool stores may carry it. If you can't find it locally, check with tftestkits.net or @Leebo for expedited shipping options. Amazon will probably take a few days. You gotta make sure to keep FC levels up.

The 10 ml test is the best option to use for daily testing. During a SLAM, you could even get away with using a 5 ml water sample, one scoop of powder, and each drop will count as 1 ppm. You'll lose some accuracy, but will save your reagents.
 
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Texas Splash

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I agree with Mike (Rancho). 10 ml is typically best for normal testing, and in a pinch the 5 ml sample will work too. For your FC to be way off, I wonder if you got the math crossed somewhere? It's easy to do. Just remember this:
5 ml sample (one scoop) - each drop equals 1 FC (not the most accurate but close enough when powder is almost gone)
10 ml sample (one generous scoop) - each drop is a 1/2 FC (i.e. 20 drops equals an FC of 10). The daily standard.
25 ml sample (two scoops) - each drop is 1/4 FC. results in extreme accuracy, but not typically needed for daily testing.

Hope that helps.
 
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Sandi DC

Bronze Supporter
Dec 16, 2019
40
South TX
Good morning and thank y'all for the replies. We will be on the hunt as soon as stores open for the product today. Eeeesh this could be a costly mistake.

Texas Splash, Oy again! I read somewhere that if 1 scoop turned the sample pink that it was sufficient. sigh... so all day yesterday while using 25ml to test, I was only using 1 scoop. On my last test last night using 10ml, I also used 1 scoop. New lesson learned. Thank you.

This morning I am disappointed to report FC is at 25 (a drop of 2.5 overnight) so I HAVE to find drops.
Water looks clear to me but sun isn't up yet.

I did send a bottle of water with my husband to test at Leslie's since he will be there looking for drops. The results will likely confuse me. hahaha... I promise to take them with a grain of salt and not freak out. :)

feeling a bit frustrated with the mistakes I have made, however I will follow my own advise and chalk it up to the school of life :). I sure do appreciate the help.
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
Mistakes, yes, we've ALL been there. :hammer: No worries. You'll get it. As for the Leslie's trip, more than anything I'd still be curious about the iron/copper reading, that's about it. They probably won't have the powder or drops you require, but if you contact TFTestkits.net they ship very quickly. As for local running around ..... good luck! I keep looking in the sky for the meteor that's coming based on how everyone is reacting in town. Just crazy - especially for anything that disinfects (i.e. bleach/chlorine). Hopefully you won't have any problems. This may be one of those very rare times where grabbing a box of liquid chlorine from Leslie's may be needed if Home Depot is out. I know HEB shelves were bare.
 
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wireform

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In The Industry
Aug 15, 2017
1,537
Spring Valley, NY
What's the worst case scenario, slam for 2 more days guesstimating your FC loss +, add that much LC to the water so you'll be keeping slam up where you possibly ought to be anyhow and in the mean time either order from tft.net or from Amazon with 2 day delivery. You will not find it in stores.
 
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Rancho Cost-a-Lotta

Silver Supporter
Apr 10, 2018
1,598
Rancho Cucamonga, CA
The 10 ml test is the best option to use for daily testing. During a SLAM, you could even get away with using a 5 ml water sample, one scoop of powder, and each drop will count as 1 ppm. You'll lose some accuracy, but will save your reagents.
I'm correcting my own post...I missed a zero above.

For the 5 ml test, each drop will count as 1.0 ppm.

Sorry...Mike
 
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Sandi DC

Bronze Supporter
Dec 16, 2019
40
South TX
A neighbor generously filled my R-0871 bottle late yesterday afternoon so I was able to get back to business.

At noon (water was drawn at 6am and kept in the fridge), my husband took a sample to Leslie's (since he was looking for R-0871) and was given the following results
FC 15
PH 8.3
TA 75
CH 450
CYA 43
IRON .2
COPPER .6

When I checked FC around 6pm yesterday I got a 16 so I added more chlorine and at 7:10 pm it was a 21.5

This morning FC was 20 with a CC of .5 and the water is clear. The difference from last tonight to today is a 1.5ppm loss. Would y'all really recommend that I need to SLAM again today? or can I begin the process of finding my other levels now and working on them? Are there any rules to rebalancing specifically after SLAM? I ask because I think I read that PH readings may not be accurate while SLAMing but I don't recall seeing an explanation as to what to expect.

I also wanted to attach files to explain our situation a bit. Our terrain is very sandy! When we had our pool dug, we had them spread the dirt from the hole over the back part of our property in hopes of leveling out the ground. It didn't occur to us that so much of that sand would blow into our pool on breezy days. We keep our vacuum in the pool at all times and I brush the tanning deck and walls at least once per week. The picture of the filters is 2 days after my husband cleaned them! He said they really aren't bad compared to what they were on Saturday, but this looks excessive for 2 days to me. Thoughts? and does he need to clean them again immediately? We also had installed septic risers (circled in red) in a close proximity to the pool on Sunday with the wind blowing toward the pool. Are dirt and sand considered organics that are going to be problematic and cause me to have to SLAM the pool frequently?
 

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Texas Splash

Mod Squad
TFP Expert
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Sandi, I see a couple concerns that you should keep in mind:
1 - While it may seem reasonable to think of a 1.5 FC loss since yesterday to be somewhat close to passing an OCLT, it really isn't. Water/air temp, amount of sunlight, potential organics or algae all play a part in that FC loss. To be sure, I would do a proper Overnight Chlorine Loss Test because your water FC level was quite low for a while.
2. You are correct that the pH will read high when the FC is over 10.
3. Your filter cartridges almost look like they have more of a orange/rust color to them as opposed to dirt or algae. When mine are dirty, they are gray color. Orange can be a sign of iron, but earlier we talked about sediment in your water too. Are you finding any rust stains in the house (i.e. sinks, toilet, laundry, etc)?
4. Speaking of iron, while we don't place much reliance on pool store tests, they sometimes have value when it comes to iron/copper. If that copper level is correct, it's way too high. In fact, whenever iron or copper exceed 0.3, the potential for side effects (color changing, stains) increases - especially when the FC and/or pH are elevated.

So for now, I'd maintain a SLAM level proportionate to your CYA. I think your last CYA (your test) was 50, so that means an FC SLAM level of 20. If your CYA is lower, then adjust according to the FC/CYA Chart. Do the Overnight Chlorine Loss Test tonight if you can. First reading before bed, then 2nd test in the morning before the sun hits the water. Leave the pump on low. Let's try to rule-out algae, then we can focus on any other adjustments from there.
 

Sandi DC

Bronze Supporter
Dec 16, 2019
40
South TX
Thank you. I will make sure that FC is at a 20 again this evening (I get a 50 CYA using the Taylor kit) and recheck in the morning.

Our home has a water softener so no rust stains in our sinks, toilets, or laundry however, we use a prefilter before the water goes through the softener as well as an extra filter on the kitchen sink. The filter at the softener allllways has to be replaced monthly and it turns orange also. The ground sand here is orange..red dirt. All Leslie's test prior to March showed 0 rust. March 3rd .1 and yesterday .2. Copper had also always been 0 until March 3rd and it was .1 and yesterday .5. The same neighbor who gave me the R0871 drops seemed concerned when I told him that when I tested the PH level from the spigot outside (not softened) that we fill the pool with that it was reading below the 7.0 level...no red or orange to it at all...it looked yellow. He tested his yesterday and it also showed very low...mayyyybe 7.0. Sorry if this is irrelevant but trying to get to the bottom of it all.