Why won’t my free Chlorine stay between 3-5. I have slammed the pool a few times this summer with success.

[gdav]

I’m so frustrated. When my pool was 1st installed (we don’t use it much) I could go weeks without having to add a thing and my chemicals stayed balanced. We have a chlorinator and I keep that on full. Last year, I couldn’t keep the water clear, it would get algae and cloudy. This year we replace the pump and that has helped. The water isn’t getting cloudy, but will start to grow green algae in about 4-5 days.

Last year the spider gasket went on my pump and the pool store said they no longer make that gasket and NOT to order a generic one on Amazon. Install a ball valve instead to open and close when I need to backwash. My filter isn’t quiet and does sound like air is getting in. Could this be the problem and my filter isn’t working efficiently? Should I replace my filter next?

Todays readings
FC. 2.5
PH. 7.5
TA. 60
CH. 250
CYA. 45

chlorine 5

 

[Bperry]

I’m so frustrated. When my pool was 1st installed (we don’t use it much) I could go weeks without having to add a thing and my chemicals stayed balanced. We have a chlorinator and I keep that on full. Last year, I couldn’t keep the water clear, it would get algae and cloudy. This year we replace the pump and that has helped. The water isn’t getting cloudy, but will start to grow green algae in about 4-5 days.

Last year the spider gasket went on my pump and the pool store said they no longer make that gasket and NOT to order a generic one on Amazon. Install a ball valve instead to open and close when I need to backwash. My filter isn’t quiet and does sound like air is getting in. Could this be the problem and my filter isn’t working efficiently? Should I replace my filter next?

Todays readings
FC. 2.5
PH. 7.5
TA. 60
CH. 250
CYA. 45

chlorine 5

Algae is always caused by too little chlorine.

 

[gdav]

Algae is always caused by too little chlorine.

I check my chlorine daily and it is always between 4-5. I have the TF test kit.

 

[jimbethesda]

I check my chlorine daily and it is always between 4-5. I have the TF test kit.

Your first post says FC 2.5. Is that a mistake?

 

[gdav]

Your first post says FC 2.5. Is that a mistake?

No. My daily chlorine is between 3-5
My Free Chlorine is 2.5 today.

I use the trouble free pool calculator and the TF test kit

 

[JJ_Tex]

I dont think you are reading the FC/CYA charts correctly. Look at my signature for the link if you need.

At a CYA of 45, we round up to 50. That means your FC should be between 6-8 most of the day and never ever ever below 4. Also feel free to run a bit hotter than the chart. Thats what I do and I never get a speck of algae, never a chlorine smell, and I even get complimented on my "low chlorine" pool that doesnt irritate their skin like other pools.

 

[wireform]

We have a chlorinator and I keep that on full.

With a 12k pool there's no reason to run it on full only due to the fact that half is getting consumed by the algae. I have a 18k pool with the chlorinator set between 3-4 and works quite well. You need to do a
Overnight Chlorine Loss Test to see whats going on and probably need to slam to get back on track.

 

[TinFoilHat]

I would also say that you need to loosen the unions on your pump and position it to be straight with the suction line. I'm not aware of a union that corrects a crooked line. That could be your air leak, if you really have one.

 

[wireform]

I would also say that you need to loosen the unions on your pump and position it to be straight with the suction line. I'm not aware of a union that corrects a crooked line. That could be your air leak, if you really have one.

There is a union that has a ball for line up but that ain't one of them.

 

[gdav]

I dont think you are reading the FC/CYA charts correctly. Look at my signature for the link if you need.

At a CYA of 45, we round up to 50. That means your FC should be between 6-8 most of the day and never ever ever below 4. Also feel free to run a bit hotter than the chart. Thats what I do and I never get a speck of algae, never a chlorine smell, and I even get complimented on my "low chlorine" pool that doesnt irritate their skin like other pools.

Ok, now I’m completely confused. My FC I’m getting is from the cylinder to 10 ml pool water. Heaping scoop of R-0870 powder, swirl to mix. It turns pink, then I add R-0871 one drop at a time swirling after each drop until clear (today was 5 drops) x .5 = 2.5

I would attach a copy of my Chlorine from this morning but I already added shock so it isn’t accurate. But this mornings test was yellow and (I have difficulty seeing the difference between 3 and 5 sometimes, that why I think it is probably in between and at a 4)

 

[wireform]

That's because we don't use the comparator block for the FC reading. It a good test quickly see if there's chlorine present but that's it. You need the dpd test for FC. Sends like you'll benefit from the magnetic stirr https://a.co/d/eiROIsK

 

[jimbethesda]

No. My daily chlorine is between 3-5
My Free Chlorine is 2.5 today.

I use the trouble free pool calculator and the TF test kit

Only FC counts. It’s too low. You probably have algae. Time to follow the SLAM process.

 

[JJ_Tex]

Ok, now I’m completely confused. My FC I’m getting is from the cylinder to 10 ml pool water. Heaping scoop of R-0870 powder, swirl to mix. It turns pink, then I add R-0871 one drop at a time swirling after each drop until clear (today was 5 drops) x .5 = 2.5

I would attach a copy of my Chlorine from this morning but I already added shock so it isn’t accurate. But this mornings test was yellow and (I have difficulty seeing the difference between 3 and 5 sometimes, that why I think it is probably in between and at a 4)

I'm not saying you are testing incorrectly, I'm saying you have bad targets for FC based on your CYA. You have been targeting 3-5 and it should be higher and why you keep getting algae. Here is a visual I put together, look at the CYA of 50 row for you:

 

[jimbethesda]

I'm not saying you are testing incorrectly, I'm saying you have bad targets for FC based on your CYA. You have been targeting 3-5 and it should be higher and why you keep getting algae. Here is a visual I put together, look at the CYA of 50 row for you:

View attachment 604833

He’s been targeting TC, not FC as far as I can tell. His current reading is 2.5. SLAM time.