High CYA

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J

jagfan

0
Apr 8, 2009
104
Orange Park, FL
Just started the BBB method a few weeks ago after finding this forum and learning my CYA is high. Below are today's test results and I'm wonderering where I should start? I will be removing water - slowly - probably to just below the skimmer, so I know I will have to do that often. I'm going to start pumping out the water when I finish this post. What do you recommend as the next step when I start refilling? Acid to reduce PH or bring up the CL level or what ? Appreciate the advice.

FC = 1
TC = 1
CC = 0
PH = 7.9
CH = 60
CYA = 125
 
The first step is to start working on getting your CYA level down.

Getting PH down is the next priority, though it may well come down as you replace water.

How does the water look? If the water is clear right now, you should start adding chlorine right away, so you don't get algae. If you already have algae, you might as well wait till you have gotten the CYA level down.

You didn't post a TA level. It would be good to know that.

Since you have a vinyl liner pool there is no need to add any CH, your current level is fine.
 
I agree with Jason, if the water is clear go ahead and get some chlorine in there...

After you refill the water to the normal level, allow the water to circulate for a couple of hours, then take another set of test results and then make any adjustments. You may see your PH go lower or higher....since you are making such small changes it may not be noticable. Will have to wait and see.

How did you decide to only drain down to the skimmer? Do you have water table issues? Or are not able to pump out the water?
 
Sorry, forgot the TA. TA is 163

Pool is sparkling and has been for several weeks.

I didn't think I could lower past the skimmer line because the pool pump needs water to work. Right now I don't have small sump pump. Sorry if I'm not using the correct terms but hope you get my gist. You can probably tell I'm a female.
 
I guess I know more than I thought I knew ; ). I was able to cover the in-line in my skimmer so all the water is pumping from the main drain to waste and the pump is working. So, I should be in business. I'm in Florida and not sure about the water table. Will I be safe emptying 2-3 feet?
 
Hey Jagfan, welcome to TFP!!

You should be able to lower 3' of water on a 6 year old liner without problems (other than the water table issues FPM mentioned!) . However, if the pool has been subjected to low pH, below 7.0, or very high chlorine/ relative to cya for any prolonged time (like over a week) you should probably not drain more than 2' at a time because the liner may have lost some of it's elasticity and might not 'snug' back into the corners properly.

Do you know how many gallons the pool holds? (doing some quick math, I figure 2' drains will remove ~ 6500 gal.)

Glad you've joined us! Listen to Jason and Ann's (FPM) advice! I hope you plan on ~ retiring the auto- chlorinator and switch to bleach for your chlorine so that you don't end up with this problem again :-D

You posted while I was typing this -- you can 'dribble the bleach into the flow from the fill line and get decent mixture/ circulation 8) Congrats on getting the ball rolling on this :goodjob:
 

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waste said:
Glad you've joined us! Listen to Jason and Ann's (FPM) advice! I hope you plan on ~ retiring the auto- chlorinator and switch to bleach for your chlorine so that you don't end up with this problem again :-D
Click to expand...

Oh yes, that's been retired for about 6 weeks now. Strictly bleach. Would love a SWG but not sure I can justify the cost right now.

I'm anxious to get my next reading.

Thanks to everyone for the great advice.
 
When removing pool water for high CYA, I read the following comment on another forum and wondered whether there is any validity to it?

"I have not tried this yet. But do you know that Cyanuric Acid has a specific gravity of 2.5? Water has a specific gravity of 1.
If this is correct according to the MSDS sheet, it seems that the best way ot dilute is to turn your filter off for about three days. this will allow your chemicals to seperate. The Cyanuric Acid should settle to the bottom of your pool. At this point you should remove some water from the bottom to reduce the levels. This may reduce the amount of water that must be removed. I will let you know what happens."
 
That isn't really true. If the pump has been running at all recently, the CYA will be mixed throughly throughout the water. If the pump has been off for weeks, there may be some separation of the water into different layers with different CYA concentrations, but I wouldn't count on it even then.
 
JasonLion said:
That isn't really true. If the pump has been running at all recently, the CYA will be mixed throughly throughout the water. If the pump has been off for weeks, there may be some separation of the water into different layers with different CYA concentrations, but I wouldn't count on it even then.
Click to expand...

I don't think it's true, either, but I'm curious. My pump has been not just off but in the house since September. (The only things that stay outside are the timer, the breaker box and 3 Jandy valves.) I re-installed everything yesterday but I haven't connected the electric. I'll pull samples from the surface and from water sucked out the MD and compare CYA when I test the pump later today. I think I closed with about 40 which is good because it is in the middle of the testing range. Watch this space! :)

I tried to post this yesterday but I killed the server in the process!!
 
It's not true. If you are going to read any further be warned that there is chemistry below! :shock:



The CYA is DISSOLVED in the water and exists as IONIC species! (Chlorinated isocyanurates, which is what you have when you have both CYA and chlorine in the water, exist as about 10 different ionic species in water.) The ions are going to be equally distributed through the water just as chlorine ions, calcium ions, bicarbonate ions, sodium ions, etc. will be. The definition of a solutions is a homogeneous mixture composed of two or more substances.
We are not talking about colloids and suspensions here (such as what happens when you overdose on clarifiers or precipitate calcium carbonate and cloud the pool) but solutions where a solute (CYA) is dissolved in a solvent (water). Even if the water was stagnant and there was no circulation the ions would move to a state of maximum randomness (and be equally distributed throughout the solution) as the second law of thermodynamics states.
I do not know where these fallacies have started but they are fairly common and I have heard conflicting ones concerning CYA from pool professionals. I was in one product seminar where the speaker said that CYA was concentrated in the top 3 inches of pool water so by turning off the main drain and only using the skimmers when you drained would remove CYA faster :shock: and I have also heard the opposite. :shock: :shock: It just goes to prove that a lot of "pool professionals" and manufacturer's reps do NOT understand basic chemical principals :shock: and possibly have never even had a high school chemistry course! :shock:

A bit of common sense and an understanding of chemistry will blow this myth right out the window!
 
duraleigh said:
I tried to post this yesterday but I killed the server in the process!!
Click to expand...
Aha! Durk is the reason for my nearly fatal depression last night! :lol: :lol:
Click to expand...

Imagine MY pain, postus interruptus is brutal....

The results are in. Samples were done blindly as I collected in identical glass jars with 'S' and 'MD' taped on the bottom, did the old shell game shuffle, and stuck 1 and 2 on them randomly. S aka 1 was scooped from the top, which is about two feet below skimmers. I was able to prime pump with garden hose (setup is self-priming when pool is full, pump sits about 6 inches below water level) and then drained MD to waste for 2 minutes and collected from waste hose for MD aka 2. Prior to this pool has been absolutely stagnant with solid water-tube type cover since September 20.

I have two tubes, as I replaced my Taylor comparator not too long ago. The walls are somewhat cloudy on the old one but that should not affect this test. To be safe, I swapped the tubes between test pairs. I tested each sample twice and all four were between 35 and 40. Surface averaged 38 and MD averaged 36. This is well within my ability to be precise and consistent in a turbidity test which is quite subjective (not really the word I want--perhaps I just mean imprecise). I tried to be absolutely consistent in meniscus levels, mix times, lighting and how I held the tube and looked at the dot. I consider these to be equal results within the limits of testing precision. I also filled each tube to 40 (where dot appears but quite faintly). A comparison of both tubes left me unable to say that one was more turbid than the other.

Myth debunked! Chemical theory upheld! There is no easier, softer way to drain out the evil CYA.
 
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