Hi all, one of those is this normal questions.

[Rich Elmer]

So background is, new pool owner, 28,000 ish gallons, in ground, SWG, in Florida, sun on the pool all day.
In short I’ve struggled to keep chlorine in the pool, originally I had an ic40 swg and as the summer rolled in from March onwards I had to have the swg on 100% to try and keep some chlorine in the pool, shocked with liquid chlorine twice a week.
Phosphate levels at 0
CYA at about 60ish
Water Temp is about 85 each day
We have had rain most days so we get overflow.
Salt is at about 4000 to try and give the swg enough to work with.
Read comments about the swg should really be sized 2x so swapped the ic40 for an ic60 and it’s running at 100% now.
Shocked it again with liquid so hoping it will hold chlorine now.
Am I fighting against the rain? And overflow? Is this normal, I thought with a swg I wouldn’t have to shock with liquid chlorine so much.
Any thoughts or observations?

 

[.ben]

You mentioned you are running the SWG at 100% but did not mention how long you are running your pump (and thus SWG). Chlorine output is a product of run time and %.

You should normally never have to “shock” a pool with a properly sized SWG, like yours.

How are you testing chlorine levels?

 

[Rich Elmer]

You mentioned you are running the SWG at 100% but did not mention how long you are running your pump (and thus SWG). Chlorine output is a product of run time and %.

You should normally never have to “shock” a pool with a properly sized SWG, like yours.

How are you testing chlorine levels?

Pump is currently set for 3am to midnight so 21hrs.

I’m testing chlorine with taylor k-1004. When I shock it it gets to 5ppm (red) and then slowly drops over the next week or so down to 1(pale pink)
Ph is always a bit high as the pool is new hovers around 7.8-8.2

Thanks for the reply

 

[Rich Elmer]

Saturday midday. Tested just now. I’m currently at chlorine 3-4ppm and ph 8.2
2skimmers are clear.
Pentair quad filter was completely cleaned and recharged with 6lbs DE powder about 1month ago. Usually clean it out every 2 months so far otherwise pop up heads don’t pop up enough.

 

[Flying Tivo]

You need a proper Test Kits Compared.

 

[Rich Elmer]

You need a proper Test Kits Compared.

Ok Thanks I’ll order a TF100 and post the results.
Even if my test kit isn’t great it seems to suggest I’m eating chlorine?
Oh and My cya tester is the pentair test kit.

 

[MichaelT20]

(Newbie here take with a grain of salt while I’m still learning too).

Chlorine gets used up by two possible things. Sunlight and nasty stuff in your water. To rule out the latter you want to do an overnight chlorine loss test:

Perform the Overnight FC Loss Test (OCLT)

The Overnight Chlorine Loss Test tells if the SLAM is finished or if you need to start a SLAM. This article says how to do the OCLT.

www.troublefreepool.com

Note you need a good test kit to do this as it requires precision!

Your other option is the possibility that there’s something wrong with your swg. But I’d start with the Oclt when your test kit arrives. Remember to turn off the swg for the test.

 

[Rich Elmer]

Ok makes sense. Once my test kit gets here I’ll do this.

 

[TampaKathy]

With a CYA of 60 your target FC is 4 with a minimum of 3...if you are letting it fall to 1, you probably have organics eating the chlorine. Assuming you fail the OCLT you will need a lot of liquid chlorine. My pool is smaller than yours (21k gallons) and it took 11 gallons of chlorine over 3 days before I passed OCLT.

 

[Rich Elmer]

With a CYA of 60 your target FC is 4 with a minimum of 3...if you are letting it fall to 1, you probably have organics eating the chlorine. Assuming you fail the OCLT you will need a lot of liquid chlorine. My pool is smaller than yours (21k gallons) and it took 11 gallons of chlorine over 3 days before I passed OCLT.

Ok, that’s good to know Thankyou for the input, much appreciated

 

[Rich Elmer]

With a CYA of 60 your target FC is 4 with a minimum of 3...if you are letting it fall to 1, you probably have organics eating the chlorine. Assuming you fail the OCLT you will need a lot of liquid chlorine. My pool is smaller than yours (21k gallons) and it took 11 gallons of chlorine over 3 days before I passed OCLT.

One question, is it ok for FC to go above 4 while trying to pass OCLT and SLAMming the pool? It just shouldn’t go below 3, correct?

 

[TampaKathy]

If you need to SLAM, you'll need to get the FC up to 24.

 

[Rich Elmer]

If you need to SLAM, you'll need to get the FC up to 24. View attachment 451771

Ah ok, got it. So it’s best to get CYA down a bit before SLAMming so I don’t have to get FC up so high. Can I use my SWG during slamming to try and keep FC high enough, or is that a no no?

 

[proavia]

No need to lower the CYA before a SLAM with CYA of 60.
Lower the pH to 7.2 first and then SLAM away.
It takes a little more chlorine to get the FC up to 24 (SLAM level for CYA 60). But after that, it really won't take any more to MAINTAIN the SLAM FC level.

 

[Rich Elmer]

Ok, that’s good to know Thankyou for the input, much appreciated

If you need to SLAM, you'll need to get the FC up to 24. View attachment 451771

Ok I got my test kit.
I’m holding off doing the Slam as we have torrential rain for the next week and the pool is just constantly overflowing right now. I presume this is the right thing to do to make my first SLAM as easy as possible? I have 30 gallons of 10% chlorine ready to go once the rain stops.

 

[TampaKathy]

On a good note, your CYA should be down when you start SLAM...less chlorine needed

 

[Rich Elmer]

On a good note, your CYA should be down when you start SLAM...less chlorine needed

Ok So I’ve just SLAM ed for 3 days and I think tonight I’m going to be good for only losing .5 chlorine overnight. So I’ll need to add some stabilizer tomorrow, and sort out ph etc. Any ideas what I should now set my IC60 SWG to to maintain chlorine levels? Previously it’s just been on 100% trying to keep up with whatever bacteria were in the pool so I don’t have a reference point to goto. Do I put it on 100% and gradually turn it down or put it on 50% and see what happens. Thoughts? I don’t really want chlorine to drop to 0 anytime soon after using 30 gallons over the last 3 days.

 

[mknauss]

With a 21 hour pump run time, I would start at 50%. and then adjust from there.

 

[TampaKathy]

I have mine at 75% for 16 hours which is probably a little high but I want to stay well above minimum, lol. 50% is probably a good starting point.

 

[Britali]

Ok So I’ve just SLAM ed for 3 days and I think tonight I’m going to be good for only losing .5 chlorine overnight. So I’ll need to add some stabilizer tomorrow, and sort out ph etc. Any ideas what I should now set my IC60 SWG to to maintain chlorine levels? Previously it’s just been on 100% trying to keep up with whatever bacteria were in the pool so I don’t have a reference point to goto. Do I put it on 100% and gradually turn it down or put it on 50% and see what happens. Thoughts? I don’t really want chlorine to drop to 0 anytime soon after using 30 gallons over the last 3 days.

When you do the OCLT make sure your SWG is off, otherwise the SWG may be covering up what you are actually losing.