My Newest Water Test

[chayne]

ok, so i think i have got this whole testing down. still having just a little bit of a problem determining if my tests look good or not. i have looked through pool school and from what i can tell these numbers look pretty good. i know my CYA is a bit high, but i am sure it will come down in the next few days with this hot Texas sun beaming down on pool water all day long. here are my results

FC-10
CC- 0
TA- 120
pH-7.6
CYA-100

 

[Mr Bruce]

CYA doesn't go away with sun. You have to drain it. I would get it at least down to 70, preferably 50. It may be over 100. Pool School - Chlorine / CYA Chart

 

[Texas Splash]

Charles, you may benefit from doing a diluted test just to confirm if your CYA is much higher than 100 as follows:

CYA Dilution Testing:
Add pool water to bottom of sticker.
Add tap water to top of sticker.
Shake.
Pour out half so mixture is to bottom of sticker.
Add reagent to top of sticker.
Shake.
Test outside with back to sun and tube at waist level.
Pour back and forth a few times to see if you get the same result.
Double the result.

Regardless, as Mr Bruce noted .... you'll want to do a partial water exchange to lower it soon. It will be hard to maintain the right (high) FC to match. I keep my CYA between 60-70 in the summer and never let it FC drop below 6 and I'm usually good all year long. Good luck, and stay cool.

 

[chayne]

I know that I am going to have to add some water either this evening or tomorrow. The sun is bringing my water down to almost bottom of skimmer about every 5 days. So I will be exchanging water over the next few days. I might go ahead and drain it down about another 4 inches or so and add water. I am off work the next 5 days so I can put some work on the pool. I just want it to be ok to swim on Sunday evening for our annual 4th of July party.

 

[Texas Splash]

Also remember that evaporation doesn't reduce CYA. Only the actual replacement of water does that. So until you can do that, ensure you keep that FC elevated. With your CYA, I would keep the FC between 10-12 and never let it drop below 8. Don't forget to try that dilution method sometime. You might find your CYA to be higher than 100.

 

[chayne]

Did you mean that my CYA might be higher than 100. You stated my FC. Just curious of something. What is the downside of the high CYA?

 

[Texas Splash]

Yes - I was referring to your CYA possibly being higher than 100. Corrected above - thanks.

 

[chayne]

What is the downside of having a high CYA?

 

[Texas Splash]

When your CYA is over 90, it presents a few main issues:
- Your target FC must always be at/above 10 which makes routine pH testing difficult
- Again, you need to keep the FC higher on a daily basis; exact FC levels can be a bit of guesswork (we don't like to guess)
- If you do get algae, then the FC level to SLAM is exceptionally higher requiring more bleach and reagents to test frequently

Overall just not very efficient water management.

 

[chayne]

Oh ok. I appreciate the info. Going to be draining water down first thing in the morning and gonna fill back to normal level. Gonna checkeep tests again. Hopefully I can get CYA down and I can make up if FC is down

 

[chayne]

after a partial drain of pool just about an inch below the bottom of the skimmer here are my newest test results. FC came down, that will not be a problem to add bleach. my CYA actually came down to 90. pH came down a little also. think all will be good by Sunday. i appreciate the help tremendously.

FC-4
CC-0
pH-7.5
TA-100
CYA-90