New to TFP,... Hig CYA and High FC

[Ken1169]

I'm new to TFP and a new pool owner as we recently purchased a home with a 12,000 gallon IG with a Cartridge filter. I want to get off on the right foot and not be reliant on the local pool store so that I can effectively keep the pool balanced and well maintained. That being said I recently took some water samples to the local pool store and got the following results:

	3/26/2016	4/2/2016
Free Chlorine	7.1	13.4
Total Chlorine	7.6	16.4
PH	7.0	7.4
Total Alkalinity	27	43
Calcium Hardness	264	293
Cyanuric Acid	231	205

After the first sample I was told to shock the pool which I suspect drove the FC up to 13 with a CYA over 200. I'm looking to get some advice as to what I should do (if anything) in order to get the chlorine and CYA levels back to recommended level (told you I was new to this). In any event, I wanted to open it up to the TFP community for any advice/wisdom.

Thanks,

Ken

 

[pooldv]

Welcome to TFP!

Congrats on taking over maintenance on your pool. The first thing you need to maintain your pool is a good test kit. We recommend a Taylor K2006C or a TF100 from TFTestkits.net. That is the one I use.

Start reading here to learn about maintaining your water, Pool School - ABCs of Pool Water Chemistry

The only way to lower your CYA is to perform a partial drain and refill on your pool. The good news is that the pool store test results are often wrong, so maybe it isn't that high. Once you get a good test kit and we see your test results we can figure out what to do next.

How does the water look?

 

[Ken1169]

Water is very clear, can clearly see the bottom of the pool. I'll order the test kit see what the results are. Thanks

 

[pooldv]

Good deal! Let's keep that water clear. Add about 1/3 of a jug (40oz) of 8.25% concentrated bleach to your pool daily until your test kit arrives. Grocery store generic or big box generic concentrated bleach with no scents and not splashless or easy pour. The rest of your numbers look fine for now.

 

[kimkats]

Ken, You are already off to a good start in taking care of your own pool in getting a good test kit! THAT and finding TFP will make sure you never get pool stored. SWEET!

Let us know when the test kit gets there and we will go from there.

Kim

 

[cowboycasey]

welcome, we will get you going

 

[Texas Splash]

Hello Ken. Welcome to TFP. You're in good hands now.

 

[tim5055]

Welcome to TFP.

As you start to read in Pool School you will find that your chlorine is actually low right now. If we assume the pool store is even close with their numbers your FC should be maintained in the 16-18 range with CYA over 200. The minimum FC is always 7.5% of your CYA and you should always target a little over that to be safe.

I started with CYA around 250 and had to maintain FC around 19 all the time.

As has been pointed out, the only thing you want to use right now is liquid chlorine. Tabs and powdered shock (TriChlor & DiChlor) contain CYA and will drive your stabilizer level even higher.

 

[Ken1169]

Ordered the test kit and will start adding the bleach today, what is the best way to add the bleach? Not sure if I should add directly into the skimmer or pour it into pool in front of the return?

Thanks for the advice.

 

[cowboycasey]

Right in front of the return is the way to go

 

[Ken1169]

Ok, just got my test kit and got the results below. I had to dilute the CYA with tap water to get the 200 reading, FC and CYA are high but proportionally seem close to being in line with FC about 10% of CYA (I believe this ratio should be about 7-8%). Water is clear and PH appears to be in good shape.

Please advise as to what my next steps should be.


Thanks in advance

	Pool Store	Pool Store	DIY
	3/26/2016	4/2/2016	4/6/2016
Free Chlorine	7.1	13.4	19.5
CC			-
Total Chlorine	7.6	16.4	19.5
PH	7.0	7.4	7.5
Total Alkalinity	27	43	140.0
Calcium Hardness	264	293	375.0
Cyanuric Acid	231	205	200.0

 

[cowboycasey]

Al right, we got some numbers

1 question dealing with the CYA, did you dilute 50% pool and 50% tap? or did you do 33% pool, 66% tap? The reason I ask as you know is the test stops at 100 and if it stopped at 100 again and you say 200 CYA it may be higher than 200.

now that we know you have CYA of 200 or more maybe, do you plan on taking water out? It looks like you would need to replace about 70% of your water, you could get away with your CYA about 60 to 80 or so.. With splash out, rain, and evaporation you will probably be down to 50 by the end of summer

Your TA is a little high but that will go down as you keep your PH down with Muriatic acid, how fast does your PH rise?

 

[Ken1169]

I diluted 50% pool /50% tap. Not sure as to the question regarding the ph as I,be only been maintaining the pool for a short time and was monitoring with test strips. My first visit to the pool store a couple weeks back resulted in me buying some checials to raise the TA so I assume that is the reason for the elevated numbers(live and learn)

any potential pitfalls to draining that much water out of the pool

 

[cowboycasey]

In your location you will want to know how much ground water you have.. but it is not a good idea to empty your pool.

most have good luck draining half your water, refilling and draining half again... That is probably the best way to do it, it will use the most water and take longer but you will not be taking all or most of the water out of your pool.

This will bring your CYA down approximately 75%, that should get you 50 to 60 CYA

Until you get to know your pool and what it does/needs you will need to test the following daily

FC
PH

Your TA will lower when you add Muriatic acid to drop your PH, as the TA lowers your PH will raise slower.

 

[pooldv]

Seems like there might be a test error on the TA. Did you wipe the tip after each drop to remove static? Hold the bottle vertically for full drop formation?

Draining and refilling half the pool shouldn't be an issue.

Here are some potential problem areas.
Do you have a deep end? If yes, keep some water level in the shallow end.
Are you in an area with a high water table? Even if yes it shouldn't be a problem to drain half.
Are you on city water? If you are on a well adding metals might be a potential issue.

Otherwise, it is time to lower that CYA to at least under 100.

 

[Ken1169]

Thanks for the info. deepest part of pool is 5.5 ft. Not sure as to the water table? How would I find out ( i'm in Charlotte NC), and we are on city water. Below are pics of my equipment. What would the process be to drain? Want to make sure I do this properly

Thanks again for the guidance

 

[Texas Splash]

Ken, that's a very nice set-up. Lots of space and very neat. So, it looks as though your filter has a drain relief at the bottom - a fairly good-sized one compared to my tiny hose spigot. So when you are ready to drain some water, you should be able to extend that blue hose out, open that ball valve at the bottom, and let it flow. Some might say that if you closed or adjusted that 3-way valve going back to the pool (closest one to us on the left in the pic), it may provide more back-pressure to help the drain go out the filter bottom quicker, but I wouldn't worry about rushing it. Just open that filter bottom drain and it should work fine. If you have the pump on high it will definitely flow quicker too.

As for your water table, you might want to contact your water district or perhaps county environmental office to see if they have any recent water table stats. Even though you may eventually have to turn-over somewhere in the neighborhood of 75% of your water to get the CYA back down to a manageable level, don't feel discouraged if you have to do it in a couple stages. Better to be safe with that pool shell than sorry. Take your time and keep us posted. Lots of folks following your thread.

- - - Updated - - -

Oh and Ken, later you may want to try to update your signature with some more specific for us okay? (i.e. type pump, type cleaner(s), any other equipment accessories attached).

 

[pooldv]

Here is a list of stuff for your signature, Pool School - Read This Before You Post

 

[Ken1169]

Thanks for the insight. Will try to partially drain and refill this weekend or early next week (expecting rain next couple days). Also want to better understand water table data before I drain. I'll keep everyone informed. Thanks to everyone on this site, I've learned a lot over the past week but still have along way to go.

also updated my signature.

 

[Ken1169]

Ok so I drained and refilled about 25%-30% over the weekend with the following results:

Before After

FC 19 13
TC 19 13
PH 7.5 7.5
TA 140 110
CH 375 275
CYA 210 150

Results were as expected with my results decreasing proportionally to the water removed. Water still is very clear. My plan is to take another 25% out and refill next weekend.