SWG Runtime for Summer in FL

Naplespool

Well-known member
Mar 26, 2017
78
Naples/FL
We will be leaving our relatively new Florida pool (4 months old) for the summer. It has a SWG and the pool will be cleaned and monitored by a service once a week. I'm leaving them detailed instructions about how much of each chemical is needed based on their weekly measurements.

Currently, the chemistry looks like this and is stable, expect the PH which varies between about 7.6 and 8.0 during the course of a week with a once a week MA addition.

The SWG runs 12 hours a day at 35% and the chlorine stays stable at about 6.5 ppm at that setting (CYA 70-80 ppm). Here are the most recent measurements.

FC: 6.5
CYA: 80
PH: 7.6
TA: 80
CH: 500
Boric: 50
Temp: 82F

It's April now and the sun will get higher over the summer and the pool will get hotter. Should I leave the SWG as it is, and let the pool company make up any chlorine shortfall on their weekly visit (my instructions are such that they will boost FC to 9.5 if the FC is 5 or less), ... or should I increase the SWG from 35% (which is about 1.7 ppm FC per day) to something higher?

A higher SWG percentage may make the PH rise more quickly.

Any ideas will be appreciated.
 

mas985

TFP Expert
LifeTime Supporter
May 3, 2007
12,381
Pleasanton, CA
With an SWG, the bottom target is at 4 ppm @ 80 ppm CYA so you have plenty of margin. I would just tell them to top off with liquid CL when it dips below 5 ppm to be safe.

But is this the first year you have owned the pool? If not, what was the SWG setting for last year during the summer?
 

Naplespool

Well-known member
Mar 26, 2017
78
Naples/FL
This is the first year for the pool, it's only 4 months old. It has taken a lot of work to figure the SWG %/runtime and also the MA consumption. Thanks for your comments.
 

mas985

TFP Expert
LifeTime Supporter
May 3, 2007
12,381
Pleasanton, CA
You might want to bump it up to 40% setting just to be safe. But why 12 hours per day? Hardly any pool needs that much run time. Even during the heat of the summer, I run my larger pool only 4-5 hours per day and mostly for solar.
 

Naplespool

Well-known member
Mar 26, 2017
78
Naples/FL
The runtime is calculated for the amount of chlorine. 22.4 oz per day from my IC40 and 50% (12 hours) runtime and 35% SWG generation. My pool needs 2.3 oz per 1 ppm of chlorine. So 35% is adding 1.7 ppm chlorine/day.

I could go for a greater SWG percent and less pump time. For example I could go to 8 hours and 60% and get the same amount as 12 hours and 40%.
 

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