Cyanuric Acid

[Sue225]

Kit is here! Readings:
FC 18
CC 0
Alk 160
ph 7.8
Hardness 175
CYA 100

Let me know what you think-pool is clear

thanks

[aylad]

Looks pretty good, except that CYA is awfully high. When you get to the point where you're ready to let your chlorine come down,do NOT let it go below 8 ppm. With a CYA that high, you;'re going to have to maintain it between 8-15 ppm in order not to get algae. This is a long thread, and I haven't looked back yet to see if partial drain/refill has been suggested, but it's still early in the summer, and it sure would be a lot easier to maintain the pool if the CYA weren't that high. DEFINITELY no trichlor pucks or dichlor shock for you!!

Otherwise, TA is a little high and pH is as well, but that puts you in a great position to lower both using muriatic acid. The process is here: http://www.poolforum.com/pf2/showthread.php?t=191

Otherwise, things are looking good!!

Janet

BTW, I deleted the duplicate post--when I moderated your last post in, there were two copies. Since we have to moderate all posts in, if you post something and don't see it show up immediately, wait a bit before reposting--it's probably in the queue.

[CarlD]

If it's a vinyl pool then Alk is not a problem. If it's concrete or plaster or tile, you'll need to lower it.

With a CYA of 100, you'll have to maintain your FC between 8 and 15--you're now a 18 so you are fine.

pH is a little high, but that may be an artifact of the high FC of 18--but it's still in normal range.

About the only thing you should do is wear last year's bathing suits as the higher level of chlorine may fade them.

In short: For a high-CYA pool, your numbers look pretty good. Try adding to drops of the # 7 reagent to your pH test before your add the 0014 reagent. That's chlorine neutralizer and two drops neutralizes about 10ppm of FC--you have nearly 20. You may get a lower pH.

If your TRUE pH is lower and you have a vinyl pool, AND you are willing to maintain a high CYA pool, then I think you are just fine and good to swim.

[Sue225]

Thank you all for your help. I am waiting for chlorine to drop to about 8-10 before I let grandkids swim. I have owned this pool for 23 summers and I never, ever had anyting like this happen before. Grateful you were here to help!
Aylad I have already drained 1/2 of the pool about 1 week ago!
It has been in the low eighties and high ninties here with a few storms. Can you make a guess as to when my chlorine will drop to around 10?
Have a blessed day!

[aylad]

Aylad I have already drained 1/2 of the pool about 1 week ago!

I know that you drained a good bit--but the CYA numbers that you've posted are still very high. So you'll either need to drain/refill some more in order to lower it, OR keep your chlorine levels high (8-15) in order to compensate for it. Which decision to make is yours--I don't know how feasible they are to you.

Can you make a guess as to when my chlorine will drop to around 10?

I would say by late today or tomorrow. It doesn't take long after a rainstorm!

Janet

[Sue225]

If you have cc does that mean something is trying to bloom? My FC is now down to 11 and cc is .5 We had bad storms yesterday and I have not had a chance to vacuum bottom of pool. Do you think that is why my cc went up to .5 from 0?
Thanks for all your help. I have learned so much about pool chemistry!!!

[Watermom]

The rain probably dropped some debris in the pool which can cause a little CC. As long as you are no higher than 0.5 you are ok. Or, you can go ahead and shock the pool and that will take care of it.

[Sue225]

CC was o this AM!!! My test vial was dirty. Washed and dried it and cc was perfect!

Question is my fc is now 8 i do not want it to go lower. How much chlorine should i add tonight to get it up to 11 since i am losing about 3 ppm each day with this heat and sun.
thanks in advance

[Watermom]

In your pool, each quart of 6% bleach should add approximately 1ppm of chlorine. So that makes it easy to know how much to add --- 3 quarts.

[StevenB92]

I slightly remember years ago I read somewhere that if the pool is calm for a while that the CYA will "float" to the top and then you can remove that water, e.g. via the skimmer, thus removing a higher concentration of CYA. Also I believe that the article/post/whatever it was suggested siphoning off the top while having a water hose in the bottom of the pool slowly adding water and "pushing" the higher concentration CYA water towards the siphon.

About a year ago a co-worker told me a pool store guy verified the idea that the CYA will stratify in a calm pool and that to remove the most CYA let the pool settle and then remove the water from the top.

I have been meaning to test my water with the pump running for the "normal" cya level and then after letting the pool sit overnight test the water from a couple inches and then a couple of feet down to see if there is any difference.

Anybody else hear anything similar to this?