Raising CYA

[mookie1010]

Hello all - I used the TFP method and testing last summer after a friend recommended this place with great success. This year, after a lot of rain and evaporation, it seems like my CYA level has dropped from the 60's last year to at least under 30 this year. All numbers are below.

Question - before I found this place, I bought a ton of chemicals recommended initially by the pool store that I still have in the garage (Cal Hypo shock and the chlorine pucks), and I'm wondering if I can make use of them now to raise the CYA and keep chlorine at normal levels.


FC - 4
CC - 0
PH 7.5
CH 240
TA 80
CYA <30

Thanks

 

[tim5055]

Welcome to TFP!!

What is your target CYA? How do you normally chlorinate?

The CalHypo won't help as it adds calcium, not CYA. But, you could be using that to chlorinate as your CH is low for a pebbletec pool.

The tabs will slowly increase your CYA. Each tab will release 2.4ppm CYA in your pool when it is fully dissolved..

To be honest, that is what I'm doing now. I needed my CYA up about 15 due to our wet winter, so I have been floating tabs to slowly bring it up.

 

[mookie1010]

Normally chlorinate using liquid bleach. Target CYA would be within the normal range, which looks to be 30-60.

 

[pooldv]

Welcome to TFP!

Understanding what is in chemicals and managing your chemistry is the key to TFPC. It is fine to use any of those products as long as you chemistry stays in line. Use Poolmath Effects of adding chemicals at the bottom to see what each adds to your water. Be sure to enter gallons at the top.

More here about what is in pool chemicals
Pool School - Recommended Pool Chemicals
Pool School - How to Chlorinate Your Pool

 

[RobbieH]

You say your CYA is greater than 30. 30-40 is a good range, especially at this time of year. When chlorinating with bleach, I would not go over 40.

 

[tim5055]

Normally chlorinate using liquid bleach. Target CYA would be within the normal range, which looks to be 30-60.

If your CYA is just under 30, then floating a tab or two will be the perfect way to fine tune it in the 30 - 40 range you want to be. Once dissolved, four 8oz tabs should bring your CYA up jus tunder 10 points.

 

[delsol468]

mookie1010 - thank you for starting this thread. I was literally was going to start this same subject. As I tested all my levels yesterday and was surprised at CYA.

FC - 4
CC - 0
PH 7.5
CH 300
TA 100
CYA 25


So.. RobbieH says not to go over 40 on CYA. I plan to put 2 pucks in the floater and see what happen over a week. Is this okay since my CH is @ 300??

 

[RobbieH]

Pucks do not affect CH, only CYA and FC.

 

[delsol468]

Awesome! Thanks..

 

[RobbieH]

To be clear, there are SOME pucks that are CalHypo, but I hardly ever see anyone with them. Most are trichlor.

 

[mookie1010]

You say your CYA is greater than 30. 30-40 is a good range, especially at this time of year. When chlorinating with bleach, I would not go over 40.

That should be less than 30.

 

[pooldv]

The CYA test can be difficult to read. The 50ppm sample is designed to calibrate your eyes and teach you how to read the test. Here are some reference photos for the CYA test.

 

[mookie1010]

FWIW, as I mentioned briefly above, I used the TFP method all last year and understand the methods - I've read all the links provided. Last summer, CYA tested very consistently in the 60-70 range, which was on the high side, but once I developed my rhythm with chlorine additions each morning, things went swimmingly (HA!) all summer. This year, we've been getting lots of rain and evaporation, and both my CYA tests were under 30, which I believe to be true.

The reason I asked the question was that I knew the pucks added CYA, but I hadn't been able to find how much, or if there were other risks associated with using them. I'll dissolve 4 in there this week and test again next week to see where that lands me.

Thanks for the advice and help.

 

[tim5055]

The reason I asked the question was that I knew the pucks added CYA, but I hadn't been able to find how much, or if there were other risks associated with using them.

That is the nice thing about Pool Math Once you plug in your pool volume there is a calculator at the bottom to show the effects of adding different things to the water. I got the number above by using your volume and looking at the results of adding 8oz (3" TriChlor pucks are usually 8oz) of TriChlor.

It looks like this:




You can select almost anything TFP would normally advise to use in your pool to see what effect it will have on your water.

 

[pooldv]

At the bottom of Poolmath is a section called effects of adding chemicals. Enter your gallons up top and info and it will tell you what will be added to the pool.

 

[mookie1010]

That is the nice thing about Pool Math Once you plug in your pool volume there is a calculator at the bottom to show the effects of adding different things to the water. I got the number above by using your volume and looking at the results of adding 8oz (3" TriChlor pucks are usually 8oz) of TriChlor.

It looks like this:

View attachment 47846


You can select almost anything TFP would normally advise to use in your pool to see what effect it will have on your water.

Aha - I guess I never made it down that far. Thanks.