Help with evaluating SWG usage...

[grace_lannister]

Hi all, I have a new pool build that was completed in Dec 2024 and have learned a lot browsing these forums. I wished I discovered it earlier in the build process so that I could have avoided certain issues.

Now that it's all done and I've been maintaining the pool for a few months now I just wanted to get your thoughts on my SWG usage. I feel it's a bit high from reading others' accounts. Currently seg runs for 5 hrs/day for a 8000 gallon pool to keep FC around 5-5.5.

Jandy Truclear SWG - ran at 50% for 10 hrs/day and keeps FC around 5-5.5
Pool - 8000 gallon gunite
Alk - 80
PH - rise quick to 8.2 or over and brought down to 7.4 every two or three days (rise caused by new plaster?)
CYA - 70
CH - 300
Salt - 3000

Does anything seem seem off or anything I should adjust?

 

[SJPoe]

If the amount of time, and the setting of the SWG is keeping your FC where you want it - I'm not sure what the question is ?

Based on some quick googling - a Jandy Truclear should produce 0.93lbs of chlorine at 100% for 24hours. Using PoolMath - at 50% for 10hours, that should result in about 2.9-3.0ppm per day in 8000 gallons, so well within the normal daily losses people generally encounter (although every pool is different).

 

[ajw22]

Welcome to TFP.

That is 3ppm per day. Sounds right for TX.

 

[woodyp]

3 ppm is my LOW end for chlorine loss in Texas, and I'm 4 hours North of you!

 

[grace_lannister]

I guess the question was, is the usage normal or on the high side and it seems to be normal. I've seen many accounts of folks with larger pools running the SWG significantly less but yeah, every pool is different. I assume once it gets blistering hot then I'd have to bump up the %?

How long should I expect this high PH rise thing to last for the new pool?

 

[ajw22]

The Truclear at 0.93 per day is small compared to a 3.0 chlorine output cell.

You are fine for the cell you have and your location.

 

[SJPoe]

Usage is such a subjective thing, and affected by so many variables, it's hard to say anything with any certainty.
My pool, in mid-Michigan, generally runs 4ppm a day in the summer. Some days more, some days less. I generally run my RJ-60+ at 25-30%, 24 hours a day, and that calculates out to about 4-4.5ppm. If I notice the FC creeping up, I turn the SWG down a notch. If it's declining, up a notch. If we get a run of really hot, sunny days...I'll maybe have to punch it up to 35 or even 40% (shock-horror!!) or it rains for a week and my FC is tickling the 12-13ppm level...

Ultimately, just getting to know YOUR pool, and how your usage patterns affect your pool's chemistry is the key. Accurate, frequent testing lets you get a handle on that unique pool personality, and once you have a goo sense of how your pool 'behaves', you'll find you can probably predict what the chemistry should be on any given day, and with the methods and knowledge learnt here, know how to deal with anything that isn't where it should be.

I don't know much about plaster pools, but I would guess your PH rise is related to the new plaster - I'll let some of the more experienced 'plaster guys' comment on that side of things

 

[Parac]

Another data point as I am just outside Houston. I bumped my output up to 3.5ppm/day a couple weeks ago and we're looking at 90 degree weather already next week so it may go higher soon.

At 5ppm you are running at the low end of target and close to minimum. Staying at the higher end of target range makes things much easier this time of year so you have more warning that you need to increase the output as your FC starts to go lower.

 

[Parac]

The K1005 test kit listed in your signature is missing the FAS/DPD test for more accurate and higher chlorine levels. The K1515 is the stand alone FAS/DPD kit that you can get for that.

For ph, I think I've seen 6 months to a year as a common time frame to stop rising from new plaster. I feel like mine was at the higher end of that range and maybe a bit over a year before I would comfortably say it settled down.

Fill water Alkalinity is highish in this area as well so you are probably just starting to get that into the reasonable range. At the rate you are adding acid, it should get to 50-60 area soon and that will help ph stay lower too.

 

[grace_lannister]

Thanks Parac. I think I will bump up the FC to to 7-8 range and adjust my SWG accordingly to keep that level.

Correct re alk in fill water. I tested it and it was 120 and you are also correct, it slowly went to 80.