First CYA Test

Just did my first test for CYA. I am using the 6 way HTH test kit from Walmart. The directions say to fill the tube until the black dot disappears and then read the level in ppm. The last mark on the tube is 30. I was at the top of the tube (just a little past the 30 mark) and could barely see the black dot. I'm guessing my level is around 20 or 25 but cannot be sure because I topped out. Is this acceptable?

Also, my FC is 1.5. Depending on the day (amount of sunlight and/or use) I have to add bleach daily to get the level back to 4ppm. My PH seems to fluctuate between 7.1-7.6 daily. My water is crystal clear (though I've only had the pool for a week).

Should I raise the CYA or keep as is?
 
Sounds like your CYA is a little low. I would suggest adding about 10ppm to your pool and then testing it again in a week to make sure you are at least at 30ppm.

Once you add the CYA, you should assume the CYA is around 30 ppm and use 2ppm as your minimum FC level ... you need to ALWAYS keep the FC above 2ppm. See the FC/CYA Chart. So maybe you should target 5-6ppm each day.
 
Also make sure you are performing the cya test correctly. Generally speaking outside with back to the sun, with the tube at about waist height. If you are holding the tube in brighter light or holding up to your eyes to "try" and see the dot, that's incorrect.

It is normal to add chlorine daily. As mentioned once you know your CYA is correct, if you are dropping below your minimum regularly move your target up. That goes back to when I was telling you I keep my chlorine a couple ppm over on the target end to make sure I always stay above the minimum even on heavier load days.
 
Also make sure you are performing the cya test correctly. Generally speaking outside with back to the sun, with the tube at about waist height. If you are holding the tube in brighter light or holding up to your eyes to "try" and see the dot, that's incorrect.

It is normal to add chlorine daily. As mentioned once you know your CYA is correct, if you are dropping below your minimum regularly move your target up. That goes back to when I was telling you I keep my chlorine a couple ppm over on the target end to make sure I always stay above the minimum even on heavier load days.

Ahhh...yes, that makes sense. Thank you!!
 
Sounds like your CYA is a little low. I would suggest adding about 10ppm to your pool and then testing it again in a week to make sure you are at least at 30ppm.

Once you add the CYA, you should assume the CYA is around 30 ppm and use 2ppm as your minimum FC level ... you need to ALWAYS keep the FC above 2ppm. See the FC/CYA Chart. So maybe you should target 5-6ppm each day.

Are you suggesting I target 5-6ppm each day AFTER rising my CYA to 30ppm or UNTIL I get my CYA to 30ppm?
 
After. See the chart. With a CYA that is 20-30ppm, the minimum is 2ppm ... you need to stay above that so target 4-5ppm.
If your CYA ends up a little higher, you may want to target 5-6ppm.
 

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After. See the chart. With a CYA that is 20-30ppm, the minimum is 2ppm ... you need to stay above that so target 4-5ppm.
If your CYA ends up a little higher, you may want to target 5-6ppm.

I check my levels each day at the end of the day. My FC is usually between 1.5-3 after sunlight and use. I target and add the necessary bleach to get the level to 4ppm before covering the pool for the night. I'll up my target level to 5 from now on.
 
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