New Pool owner in New Zealand

[johnw11]

Hi,

I live in the Wairarapa, New Zealand, generally warm summers, temperature often in the 90s, with cold winters, often freezing over night.
Bought a house last year with a pool, approximately 17,000 gallons. I did not do much with the pool last year and over winter it went green. I have just drained and cleaned the pool and now in the process of filling it, probably another 2 days to go.

I have no experience of pools so this is a total learning curve for me. I have gone out and purchased liquid chlorine (13% strength) and the closest I can find to CYA called Bluewater Stablised Pool & Spa Chlorine (active ingredient is Sodium Dichloroisocyanurate Dihydrate). I am waiting for the water to get to the height of the skimmer pool so I can turn on the pump and filter.

 

[Texas Splash]

G'day and welcome! As we know, new water won't have any CYA (stabilizer), so you'll want that for sure. The Sodium Dichloroisocyanurate Dihydrate does have some stabilizer in it, but not in full strength as cyanuric acid as a major ingredient. You may wish to shop around a bit more or online. Do you have one of the preferred test kits from Clear Choice Labs? They are the best source for your region. Others from your area will chime-in soon. Also, since you just drained the pool to remove algae, there may be residual algae in the lines. You may need to perform a SLAM Process to be sure to remove it all, or at the very least do an Overnight Chlorine Loss Test to ensure any residual algae has been killed so you don't end-up right back where you started. But we'll be glad to help you with either of those as needed.

Make sure to review our ABCs of Pool Water Chemistry and update your signature when you can as well. Nice to have you with us.

 

[Arizonarob]

 

[johnw11]

G'day and welcome!

Make sure to review our ABCs of Pool Water Chemistry and update your signature when you can as well. Nice to have you with us.

Hi Texas Splash.

Many thanks for the welcome. I have updated my signature with my pool details.

I have ordered the CCL test kit today, but that has to ship from Australia so may take a few days. At the moment all I will have are those simple test strips.

As it is the middle of summer here, and we have all the relatives coming to visit us for New Year, is the pool usable if I put some Chlorine in as per the manufacturers instructions? It says for every 2600gallons to add 14fl oz. Note these amounts are approx as the actual amounts are in metric.

 

[Texas Splash]

is the pool usable if I put some Chlorine in as per the manufacturers instructions?

Sure, you can swim as long as the water is clear enough to safely see the bottom and the FC is not over the SLAM/Shock level for your current CYA as noted on the FC/CYA Levels. I think you are fine on both counts. Until your kit comes in, I would watch two things fairly closely each day:
1 - PH to ensure it's in the 7.4-7.7 range. If it creeps to 8.0 or more, bring it down with some muriatic acid
2 - Maintain the FC between 3-5. Never let it drop below 2. Once your kit arrives, you'll be able to balance the FC as noted on the FC/CYA Levels.

Practice with the PoolMath tool (or APP) to become familiar with how to calculate dosage amounts and you'll do fine. Happy New Year!

 

[johnw11]

Hi

I have finally got my testing kit from CCL and also the time to try it out. These are the readings I have today.

CYA=35
FC=22
CC=2
ph=7.8 (The testing notes say if FC is high then it will show a reading of 7.8)
TA=100
cH=100

Pool maths tells me that FC=22 is too high and I just have to allow the sun to reduce it.
TA =7.8 tells me to add 916g (32) of Dry Acid to reduce to 7.4
cH=100 tells me to add 12252g (432oz) of Calcium Chloride to increase to 270

Have I understood the readings correctly?

 

[johnw11]

I have a question about Pool Maths.

I enter my readings and click Done on each entry but when I go back to the summary page all the readings are blank? Is this correct, am I doing something wrong, or is this where I need to upgrade to Premium service?

 

[mknauss]

Great job on the test results.
Do not worry about the pH right now. As long as it is 8 or below you are fine. It is actually helping to protect your plaster with the low CH.

Do add some calcium. The amount you show is fine but start with half that amount and retest. Allow the FC to drop naturally and follow the FC/CYA Levels. Use 40 ppm as your CYA.

The free version of the app does not store data. So you need to upgrade if you wish to store the data.

 

[bmoreswim]

The one parameter of concern is the CC of 2. Anything above .5 is reason for concern enough to SLAM your pool. A SLAM is a specific process to keep FC levels high until the 3 goals are met.

Here is a good article on the process. SLAM - Shock Level and Maintain - Trouble Free Pool Once you confirm your numbers, you will want to follow this process very carefully. Deviations can cause slow or no progress of the process.

The first step is to run an Perform the Overnight FC Loss Test (OCLT) - Trouble Free Pool This will tell if FC is being actively lowered overnight while no other reasons except algae would be the reason. It eliminates the daylight consumption of FC from the equation.

I would double-check your FC and CC levels prior to slamming to ensure the CC number is correct. I don't doubt it since you had green water and you now have high FC. High FC is killing algae and, simplified, the algae killing raises the CC levels until the killing subsides and the sun has a chance to burn off the CC's. If in fact your CC is that high, the one item I'll want to get a second opinion on is what to do with your pH. pH is supposed to be lowered to 7.2-7.5 before the SLAM. But you already have high FC which affects your pH reading.

 

[johnw11]

Great job on the test results.
Do not worry about the pH right now. As long as it is 8 or below you are fine. It is actually helping to protect your plaster with the low CH.

Do add some calcium. The amount you show is fine but start with half that amount and retest. Allow the FC to drop naturally and follow the FC/CYA Levels. Use 40 ppm as your CYA.

The free version of the app does not store data. So you need to upgrade if you wish to store the data.

Hi Marty,

Thanks for the guidance. App upgrade purchased today.

 

[johnw11]

The first step is to run an Perform the Overnight FC Loss Test (OCLT) - Trouble Free Pool This will tell if FC is being actively lowered overnight while no other reasons except algae would be the reason. It eliminates the daylight consumption of FC from the equation.

I would double-check your FC and CC levels prior to slamming to ensure the CC number is correct.

Hi bmoreswim

Many thanks for the guidance. I will be redoing the tests today. As I'm new at this I want to make sure the readings are correct.

I will also do a OCLT test tonight. That means an early start as sunrise is 6:30am here at the moment. I'm not really a morning person.

One thing I did not mention is that about just over a week ago the pump bearing seized and was not working for 2 days until I got get the repair done. During that period I just put extra chlorine into the pool as the temperatures were in the low 90s.

 

[johnw11]

Test results done from today. No chemicals have been added since the reading yesterday.

CYA=35
FC=14
CC=0
pH=7.4
TA=75
cH=100

I wll try and do the OCLT test tonight.

 

[johnw11]

Test results from today. No chemicals have been added since the reading yesterday.

CYA=35
FC=7.5
CC=0
pH=7.4
TA=80 (I did the sensitive test today which is more accurate for figures less than 100
cH=100

So tomorrow Monday I want to go out and track down the Calcium Chloride to amend thr cH figure
I did not get a chance to do the OCLT test last night as we got back too late.

 

[Texas Splash]

Good thing is you seem to be getting the testing down since the numbers seem reasonable and consistent. Even though you were not able to do the Overnight Chlorine Loss Test, I suspect something is brewing (algae). Why? Because 2 days ago your FC was 14, and the next day it was 6.5 less. We generally don't like to see more than 4 ppm of FC lost in a 24 hr period. Anything more than 4 in 24 hrs means either there is heavy organic/oxidation activity, or perhaps not enough CYA to protect the FC from the sun. It is also true that when the FC is elevated, it will fall faster since the excessive FC doesn't have enough CYA to bond to.

So let me ask .... how does the water look? Cloudy, hazy at all? Can you see the bottom in the deep end okay and clearly (i.e. a coin on the floor)? I would still do the Overnight Chlorine Loss Test to confirm.

Lastly, I would recommend using the PoolMath tool or APP to review all your test results and make note of your CSI. You'll need the water temp for that as well. A CH of 100 with your current TA and pH tell me your CSI may be more negative than you want at the moment (corrosion to plaster likely). If so, letting the pH rise to about 7.8 might help quickly, and/or you may need to add more calcium. Just keep an eye on that. Have a good day.

 

[johnw11]

So let me ask .... how does the water look? Cloudy, hazy at all? Can you see the bottom in the deep end okay and clearly (i.e. a coin on the floor)? I would still do the Overnight Chlorine Loss Test to confirm.

Lastly, I would recommend using the PoolMath tool or APP to review all your test results and make note of your CSI. You'll need the water temp for that as well. A CH of 100 with your current TA and pH tell me your CSI may be more negative than you want at the moment (corrosion to plaster likely). If so, letting the pH rise to about 7.8 might help quickly, and/or you may need to add more calcium. Just keep an eye on that. Have a good day.

Thanks Texas Splash

Yes the water is very clear and I can see anything on the bottom. The pool never looks really really clear as it is not painted a nice bright blue but is an old light grey. I hope to paint the pool next spring if I have the budget.

I really hope to get the OCLT done this evening.

Trying to trackdown some calcium chloride to work on the CH today.

Here are some photos of the pool. The 2nd photo is looking straight down into the deep end. As you can see the surface is not in great condition. That is after we had drained it fully and cleaned with a water blaster and sprayed a light bleach solution onto it.

 

[johnw11]

Tests for yesterday and this morning I did the morning test for the OCLT

CYA=<35 (The amount of water in the test does not allow for it to show a lower reading than 35)
FC=7
CC=0
pH=7.4
TA=80
cH=100

Morning reading
FC=7.5

As I assume the FC cannot go up then I am putting the small increase down to a slight variance in the test.

I could not get any Calcium Chloride with no stock until next week, so I'm going to a larger town nearby to try and get some from there.

 

[bmoreswim]

Agreed on the FC testing error variance. That will get better with time. Do you have a Speedstir or similar? They are wonderful at creating repeatable test results easier. Certainly no need for a SLAM.

And back to TS's comment. If you can't find CH soon, I'd let your pH rise to 7.8-8.0 which will help your CSI move from ~-.7 to ~-.3 or ~-.1 depending on pH. I used 85 deg. F for water temp.

 

[johnw11]

Hi bmoreswim

The problem I have with the FC test is trying to accurately measure the powder. I am using the CCL test kit. It says a heaped spoon (which they supply). I think the size of the "heap" varies day to day. I wish they had a slightly larger spoon so that you could have a flat spoonful.

I got some Calcium Chloride today and added 4.4lb (2000g) so I can measure the change. I have another 4.4lb I can add tomorrow. Pool Maths is telling me to add 26lb so I will do it over the next few days as I can get some more Calcium Chloride in a couple of days. The container for the CC says to add 6oz per 2641 gallons (these are all rough calculations as all my measurements are in metric) to raise by 10 points. So the amount of CC I have added should raise by 20

 

[bmoreswim]

The size of the heap doesn't really matter. The true goal of adding that powder is to add enough for not all of it to dissolve. So if there is at least a crystal or three that has not dissolved after stirring, you have added enough. More doesn't matter (within reason I suppose). The reaction will be the same regarding the color as long as the water is saturated with the powder.

Perfect on the CH approach. I would recommend referring to calcium chloride by the full name or CH. CC used on the site refers to combined chlorine.

 

[johnw11]

Reading today after adding some CH. I added 4lb 6oz of CH and this should have added 20 points to the reading according to the instructions on the pack.

CYA <35 (that is lowest the test shows)
FC=3.5
CC=0.5
pH=7.6
TA=70
CH=125

CSI = -0.48

Temperature was 79.

So the CH is slightly higher than I expected, but then my estimate of 17,000 gallons for the pool maybe incorrect.

So today I will be adding CYA, Chlorine, and CH.

Note all the amounts below are rounded as I work in metric.

CYA I will be adding 23oz
CH I will be adding 4lbs 6oz
Chlorine I will be adding 8.5 fl oz

I will also track some some Dry Acid to work on the lowering the pH if I have to.

Do I need to worry about adding these chemicals at the same time, or should I separate the timing of adding these?