High FC loss

[Debbie17]

Hi All,
I have some questions and would love your feedback.

1. I have a liner pool, last year I didn’t pay attention to CH at all but I’m wondering if I should be testing and adjusting because I have a heater. If so, what is the ideal range?

2. Is there a better CYA test than the one in the Taylor kit? It seems subjective to me and I really want an accurate reading. I’m losing 5 - 7ppm of FC during the day and that seems like ALOT to me. Is that a normal amount? My pool is in full sun all day and I know that plays a big role. What is an average FC loss per day? I keep reading my CYA at 40/50 so I don’t want to increase it. I test every evening and morning and I’m not losing any FC overnight.

Advice please!

 

[YippeeSkippy]

Hi Debbie
Yes, heaters often need calcium to help protect the heater core. Check your manual.

No, that CYA test is the best way even though its subjective. Remember that you can pour the fluid back in the bottle and do it again and again..
Kimkats taught me a trick- pour it to the lines exactly 100, 90, 80, and so on and glance at it while standing outside, with the sun at your back. Don't stare because if you stare you'll imagine you see it. Glance and look away.
Try that and see if it helps.

Maddie

 

[Sunnydaze]

5-7ppm per day is excessive. Especially in MA with CYA at 40-50. I'm in AZ and losing about 2.5ppm per day right now.

Are you testing with the FAS DPD test?

 

[Texas Splash]

Debbie, unless you had a pool party or something, an FC loss of more than 4 ppm in 24 hrs is reason for concern. If you recently opened, I would suggest you perform an Overnight Chlorine Loss Test just to be sure there is no algae still hiding in there. That is an excessive FC loss.

 

[Debbie17]

5-7ppm per day is excessive. Especially in MA with CYA at 40-50. I'm in AZ and losing about 2.5ppm per day right now.

Are you testing with the FAS DPD test?

Yes, That is the test I use. 2.5ppm I can manage!!!! I’m thinking my CYA is not as high as I think. Maybe I’ll take a sample to the Pool Store so I can compare results.

 

[Texas Splash]

Maybe I’ll take a sample to the Pool Store so I can compare results.

I would not recommend that. I know it's temping - very tempting. But their testing is often incorrect. There's no reliability. You have a great test kit, you just need to develop confidence in that particular test which can be intimidating. Below are my notes if it helps.

Proper lighting is critical for the CYA test, so you want to test for CYA outside on a bright sunny day. Use the mixing bottle to gently mix the required amounts of pool water and R-0013 reagent, let sit for 30 seconds, then gently mix again. Recommend standing outside with your back to the sun and the view tube in the shade of your body at waist level. Then, begin squirting the mixed solution into the skinny tube. Watch the black dot until it completely disappears. Once it disappears, record the CYA reading. To help the eyes and prevent staring at the dot, some people find it better to pour & view in stages. Pour some solution into the viewing tube, look away, then look back again for the dot. Repeat as necessary until you feel the dot is gone. After the first CYA test, you can pour the mixed solution from the skinny view tube back to the mixing bottle, gently shake, and do the same test a second, third, or fourth time to instill consistency in your technique, become more comfortable with the testing, and validate your own CYA reading. Finally, if you still doubt your own reading, have a friend do the test with you and compare results.

 

[Debbie17]

Debbie, unless you had a pool party or something, an FC loss of more than 4 ppm in 24 hrs is reason for concern. If you recently opened, I would suggest you perform an Overnight Chlorine Loss Test just to be sure there is no algae still hiding in there. That is an excessive FC loss.

I’ve been performing the OCLT test every evening since I opened the pool and have and have not had any FC loss overnight since completing my slam (my slam did take a lot longer and I do believe algae was hiding somewhere but my persistent cleaning/scrubbing eventually got it). I did have a pool party on Sunday and I had an FC loss of 7ppm that day. Still seems very high to me which is why I’m thinking my CYA is not what I think it is. I was hoping there was a different test I could use.

 

[Texas Splash]

Parties can be a wildcard. Swimmers often slather oils, sunscreens, etc which can linger in the system/filter and consume a bit of chlorine. Hopefully that's all it is. But use the notes above to test the CYA one more time. If you find the CYA is only 30 or 40, you certainly can increase it. As long as you are sure of the past OCLTs, you "should" be algae free.

 

[wireform]

A pool party is disastrous to FC but can be rectified immediately with liquid chlorine and when done it'll self correct that demand. You need to be absolutely sure the slam ended and I recommend one extra day after a good OCLT but that includes ALL THREE CRITERIA TOO.

 

[Debbie17]

I would not recommend that. I know it's temping - very tempting. But their testing is often incorrect. There's no reliability. You have a great test kit, you just need to develop confidence in that particular test which can be intimidating. Below are my notes if it helps.

Thanks so much! I will give this a try.