Hi from Virginia, new pool owner with high CYA

[55gibber]

Greetings all! I've been reading posts from this site on and off over the past year or so. A little over a year ago we moved into a new (old) house that came with a pool, but I have no background/experience in pool ownership / maintenance. Mainly relied on the local pool store last year and by and large didn't have any problems. Installed an automatic pool cover which has been working well, though it did cost a fortune. The one thing that has me concerned is very high CYA levels (based on tests from 2 different pool stores) - last year they ran in the 200's and this has continued this year so far. Spent a lot time reading about this over the past couple of weeks so I know I need to stop using the pucks, and probably will need to do some water replacement. Part of what's holding me back is that my water, both last year and this year, seems crystal clear - no algae or cloudiness. There's part of me that hates to treat a number when everything appears to look good.

BTW, I just bought my first Taylor K-2006. Need to adapt the CYA method given my high levels so don't have an accurate reading yet.

So, my first few questions are:
1) the chlorine / CYA charts don't go up to my high levels.....so not sure what I should target for my FC
2) how much bleach can I safely add at one time?
3) given that my pool has looked so good since I've owned it with these high CYA levels, is it reasonable to adopt a more gradual approach to lowering the CYA than a drastic drain/refill? Or am I just lucky that no-one has become sick since my chlorine levels may have been enormously insufficient for so long, and I need to deal with this ASAP?

Thanks!

 

[OTPirate]

Greetings to you! IMO you are going to need to drain. I'm glad you have decided to stop using pucks. Try using the diluted CYA test to test Please explain how to dilute CYA test if over 100 your high CYA and please post test results liek this:

FC - Free Chlorine-
CC - Combined Chlorine-
pH-
TA - Total Alkalinity-
CH - Calcium Hardness-
CYA - Cyanuric Acid (stabilizer)-
Let's not worry about how much bleach you can safely add til we see those test results.

Take care!

 

[55gibber]

Thanks for the quick reply. I'll update with test results when I get home tonight. Thanks again.

-Jason

Greetings to you! IMO you are going to need to drain. I'm glad you have decided to stop using pucks. Try using the diluted CYA test to test Please explain how to dilute CYA test if over 100 your high CYA and please post test results liek this:

FC - Free Chlorine-
CC - Combined Chlorine-
pH-
TA - Total Alkalinity-
CH - Calcium Hardness-
CYA - Cyanuric Acid (stabilizer)-
Let's not worry about how much bleach you can safely add til we see those test results.

Take care!

 

[Donldson]

Welcome to TFP! As OTPirate said, an accurate reading of those levels will be the first step, but here are a few general answers to your questions:

So, my first few questions are:
1) the chlorine / CYA charts don't go up to my high levels.....so not sure what I should target for my FC That's because you can't really run a pool properly as you get above 100. Minimum FC is 7.5% of the CYA level so you can do the math if you want, but it really gets to be a bit unreasonable as you get above the double digits
2) how much bleach can I safely add at one time? As much as will take you to to the proper SLAM level for your CYA
3) given that my pool has looked so good since I've owned it with these high CYA levels, is it reasonable to adopt a more gradual approach to lowering the CYA than a drastic drain/refill? Or am I just lucky that no-one has become sick since my chlorine levels may have been enormously insufficient for so long, and I need to deal with this ASAP? I wouldn't wait. You might be lucky enough to just have water naturally inhospitable to algae, or you might be sitting on a powder keg. If your CYA is 200, for example, your FC is not considered 'safe' if it is below 15. Might as well get it fixed now and never have to worry about it again.

 

[55gibber]

Test results from 630AM today

(Chlorine tested at 0.5 ppm dilution)
FC - 5
CC - 0.5 (I guess really it's somewhere between 0 and 0.5 given my sample size)
pH- 7.6
TA - 130
CH - 100
CYA (dilution method) - 180? 140? I first thought 180 then realized I could still see the black dot though it was quite faint. Couldn't see it at all at 140

Thanks again for all the help everyone - I need it!
Jason