Am I using too much liquid chlorine, not enough?

[ejs873]

On the FAS-DPD, I have the TF100 kit, but it is the powder you dissolve then use the drops to make it clear. I believe it is the same process on the K-2006.

I have salt water, so I only use liquid chlorine when I need to quickly add chlorine (pool parties, had the SWCG set too low, etc.). I have my SWCG set to make ~4 FC per day and that has been working fine for me the last few weeks. If yours is also using 4 FC a day, that would be about half a gallon of 10% chlorine per day.

A gallon of 10% liquid chlorine in your pool will add FC of 9. Either your chlorine is weaker than advertised, or you have algae burning up the chlorine as well (even if you cant see it).

So, Friday night I did the OCLT test, results below. It must be that my pool is blasted with sun from sunrise to around 630pm that the chlorine burns off so fast. I think ill do 1/2 the chlorine in the morning and 1/2 around 6 to keep the levels more stable.

Friday 9pm: FC 5.8, CC 0.2
Sat 6am: FC 5.6, CC 0.2
Sat 11am: FC 3.4

 

[JJ_Tex]

Great news that you passed the OCLT and do not have algae. Please do make sure you are following the FC/CYA chart (link in my signature if you need) so that it stays that way. All of the numbers you posted are below the Target FC for a CYA of 50.

If it were my pool, I would dose it to FC of 9 that way it stays most of the day in the FC 6-8 range and well above the minimum of 4. People get worried about FC numbers that high, but you are safe to swim up to SLAM levels (20 FC). If it makes you feel better, mine is at around 9 right now and we all went swimming yesterday. You can even look at my logs and I've been between 7-13 all swim season with no issues with chlorine smells, red eyes, bleached suits, etc.

I would also consider bumping up by CYA to 60 and adjust up the FC accordingly, if the sun is burning off that much chlorine.

 

[AK-]

Great news that you passed the OCLT and do not have algae. Please do make sure you are following the FC/CYA chart (link in my signature if you need) so that it stays that way. All of the numbers you posted are below the Target FC for a CYA of 50.

If it were my pool, I would dose it to FC of 9 that way it stays most of the day in the FC 6-8 range and well above the minimum of 4. People get worried about FC numbers that high, but you are safe to swim up to SLAM levels (20 FC). If it makes you feel better, mine is at around 9 right now and we all went swimming yesterday. You can even look at my logs and I've been between 7-13 all swim season with no issues with chlorine smells, red eyes, bleached suits, etc.

I would also consider bumping up by CYA to 60 and adjust up the FC accordingly, if the sun is burning off that much chlorine.

I also run my chlorine above target. I dose my pool to have my lowest level of FC at the lower end of the target for my CYA and even with that yesterday I was 2ppm below the lower end of target due to bather load. If I was aiming my lowest levels to be the minimum I would be in algae territory right now.

In an LC pool I wouldn't raise the CYA to 60 unless you are having issues keeping your chlorine during the day.

 

[ejs873]

Great news that you passed the OCLT and do not have algae. Please do make sure you are following the FC/CYA chart (link in my signature if you need) so that it stays that way. All of the numbers you posted are below the Target FC for a CYA of 50.

If it were my pool, I would dose it to FC of 9 that way it stays most of the day in the FC 6-8 range and well above the minimum of 4. People get worried about FC numbers that high, but you are safe to swim up to SLAM levels (20 FC). If it makes you feel better, mine is at around 9 right now and we all went swimming yesterday. You can even look at my logs and I've been between 7-13 all swim season with no issues with chlorine smells, red eyes, bleached suits, etc.

I would also consider bumping up by CYA to 60 and adjust up the FC accordingly, if the sun is burning off that much chlorine.

Cool, I will try and bump up the CYA, if I can find any tablets! thanks again!

 

[JJ_Tex]

Cool, I will try and bump up the CYA, if I can find any tablets! thanks again!

You can also buy stabilizer, I just bought some yesterday from walmart for $10 or so. Before you add, be sure that your CYA is truly at 50 so you do not overdo it, since as 60 is about as high as you ever want to go even with full sun all day.

 

[ejs873]

You can also buy stabilizer, I just bought some yesterday from walmart for $10 or so. Before you add, be sure that your CYA is truly at 50 so you do not overdo it, since as 60 is about as high as you ever want to go even with full sun all day.

Will do. Checking the CYA seems pretty subjective to me. How do you check it? I make sure Im outside with good light behind me and add the solution until i cant see the black dot at all with 1 eye. Looking down through the liquid. I know test strips are the devil on this site but i still use them when I need a quick number or to verify my other tests. My strips have a 30-50 range color for CYA and I have been falling into that when my liquid test is about 45.

 

[mknauss]

How do you check it?

When you do the CYA test, try this next time.

Once you have your solution ready, back to the sun, etc. Fill the vial to a line, say 80, lower the vial to your waist level and glance for the dot, you see it, add solution to the 70 line, glance, see it, repeat until you no longer see it with a glance. Then use the CYA value one step above the line you read. So if you stopped at 50, use 60 ppm CYA.

The vial is in logarithmic scale. So it is not viable to interpolate between the lines. Just use the whole numbers, such as 50, 40, 30, ....

 

[ejs873]

When you do the CYA test, try this next time.

Once you have your solution ready, back to the sun, etc. Fill the vial to a line, say 80, lower the vial to your waist level and glance for the dot, you see it, add solution to the 70 line, glance, see it, repeat until you no longer see it with a glance. Then use the CYA value one step above the line you read. So if you stopped at 50, use 60 ppm CYA.

The vial is in logarithmic scale. So it is not viable to interpolate between the lines. Just use the whole numbers, such as 50, 40, 30, ....

This is great, thanks