FC loss everyday, Please Help!!!!

[Kaspergbge]

Hello,
I am having a very hard time trying to even get to the Target Free Chlorine level of 6 every day and maybe I am just just losing this much chlorine everyday and it's normal, but I figured I would check. Again new pool owner, so I am trying to figure this out.

In the mornings I test and my numbers are pretty equal except for FC. My PH runs at 7.2, TA is 90, CH is 250 and CYA is 50. My FC runs anywhere from 1 to 3 everyday. I add the recommended liquid chlorine off of the Pool Math app. Then the next morning it is around 3 again. Could and should I be losing that much Chlorine everyday? Anything I can do to prevent that. I do not have a cover and I am located in the midwest. It seems like I am going through a gallon of 12.5% liquid chlorine everyday. Thanks for the help.

 

[mknauss]

With a 27K gallon pool, a gallon per day of chlorine would be the bare minimum. I would suggest aiming for high target level for your CYA -FC/CYA Levels

 

[Newdude]

This is still the peak season with relatively long days and a high sun angle. (Although both lower a skootch each day). Peak season daily loss may be 4, or even 5 in the warm climates. It'll will sloooooooowly decrease each day for the rest of the season.

 

[Brian PacNW]

Just to check… Are you actually reaching 6 ppm a bit after dosing?

 

[Mdragger88]

Average loss can be anywhere from
2-5 ppm/ day - use more chlorine. Aim for high target or a scootch above to be sure you’re covered.

After ensuring your doses actually hit your target,
If your daily loss exceeds this you may need to do an Overnight Chlorine Loss Test to rule out organics consuming your fc.

 

[wjr75]

I burn 3ppm liquid chlorine per day with a CYA around 48. I have 20k gallon pool in Chicago suburbs. When I have the cover close I only burn 1ppm per day. I also aim for the high end or a little over of the CL/CYA chart.

 

[Kaspergbge]

Just to check… Are you actually reaching 6 ppm a bit after dosing?

Today I got to 5. I just checked.

 

[Kaspergbge]

Average loss can be anywhere from
2-5 ppm/ day - use more chlorine. Aim for high target or a scootch above to be sure you’re covered.
View attachment 526062
After ensuring your doses actually hit your target,
If your daily loss exceeds this you may need to do an Overnight Chlorine Loss Test to rule out organics consuming your fc.

Ok. Thanks. I will run the overnight test and see what I have. Thanks.

 

[Brian PacNW]

Today I got to 5. I just checked.

If you are attempting to dose to 6 ppm and only getting 5 ppm, then likely your liquid chlorine has degraded due to age or heat. Best to measure ~30 minutes after dosing to get the actual pool free chlorine concentration prior to OCLT; if you only trust the nominal chlorine percentage you'll get an artificially high drop in the morning.

 

[Newdude]

And as Mdraggerr said in post 5, a 5FC is begging for trouble. How you gonna stay above minimum (4) when were all losing 3 or 4 ppm a day ?

You're not, that's how.

It's the bullet train to Swampville.

Dose to 8 or 9 until the daily loss winds down. If you're only losing 1 or 2 a day, 7 leaves you with wiggle room to spare at the end of the day.

 

[kellyfair]

Remember, you are safe all the way up to SLAM level. So take it a couple of points higher than target range.

 

[Getitrite]

If you are attempting to dose to 6 ppm and only getting 5 ppm, then likely your liquid chlorine has degraded due to age or heat. Best to measure ~30 minutes after dosing to get the actual pool free chlorine concentration prior to OCLT; if you only trust the nominal chlorine percentage you'll get an artificially high drop in the morning.

When I began full on TFPC 3.5 years ago, I went all liquid chlorine (12.5%). The product I used was fresh, so I "trusted" the concentration (+/-), and calculations of the Pool Math app.

However, dosages were not giving results I expected. I made another estimate of water volume. After some test/dose/test trial and error sequences, my conclusion was that the pool had more water than I gave it credit for. Since making that correction in Pool Math, dosages/results (of all chemistry parameters) have been very close to calculations.

So - Bottom Line - The Water Volume of my pool in the app was the culprit.

 

[wjr75]

I know a lot of people will say you don't need it but I use 6 oz of Polyquat 60 algaecide per week as an insurance policy for my 20k gallon pool. If you are bumping up against the low CL level this will give you some breathing room. I have not had any algae blooms in years since doing this.

 

[kellyfair]

If you aim higher than minimum (and I would say aim a point or two higher than target range) you won‘t need to worry about bumping against minimum.

But to each their own. I do use algaecide every couple of weeks - but only a specific one because it lowers the surface tension of the water, so wasps drown. I seriously hate wasps with every fiber of my being, and there are a lot around here.