Good test values, still occasional light algae dusting

[red-beard]

On the hot tub, 6 of my 11 returns are in the spa. But that does not mean the bottom of the spa water is circulated. My automation system switches to spa mode once a day for 15 minutes. This circulates water through the spa drain line once a day with fresh chlorinated water, and fully mixes the spa water. The temp setting is "off" unless I'm using the spa.

Although my pool feels like it is in "spa" mode most days in summer (90-92 degrees).

 

[bware]

I'm also in the Houston area (Energy Corridor). Using your pool size 15,500 gallons, 6 pump run hours and SWG, at 60% you generate 1.6 ppm of FC a day. There is a function in pool math in the "adding chemicals" which allows you see how much chlorine you are adding.
At 70 ppm CYA in Houston, I will say that is not quite enough.
At 8 run hours, you will get about 2.2 ppm FC. That is closer to what I run.
It has been very very sunny recently, since the June/July rain stopped. I think the extra 2 hours a day will help. I think setting the SWG to 75% will also help. That will give you a boost of 2.7 ppm FC a day.
My other suggestion is to try to be closer to the upper end of the FC range. The FC range is 3-10 ppm with the "target" of 5.
I setup my pool to be around 8.5-9 in the morning on a sunny day, so that I'm still in the range at the end of the day. You are running the SWG hard during the sunny part of the day, which is good. But you may want to boost your FC so that you start the morning around 8 ppm. You can get the FC up by extending your pump hours for a few hours for a few days.

SWG is running at 85% now. I meant before this summer I never ran it over 60. I’m running pump 10-6 now and just checked FC, 3:30pm, it’s at 8 now and still no CC.
Gonna keep close eye on it, ‘ cause I’m not thrilled at upping the SWG much higher. Prob dose it with a little bleach if I leave for a few days. Thanks for all your input.

 

[bware]

Sorry this was so confusing, and I definitely did not mean to run your blower! It sounds like you are already circulating you hot tub water whenever the pump is running. We run our pump continuously during daylight hours at 30 GPM. We are draining from pool skimmer and hot tub drain and returning water to both the pool and the hot tub. So, our hot tub water is never just sitting still now during daylight hours.

No problem, thought that’s what you meant. Think running pump some extra time will get me there. Thanks for all your info.

 

[red-beard]

SWG is running at 85% now. I meant before this summer I never ran it over 60. I’m running pump 10-6 now and just checked FC, 3:30pm, it’s at 8 now and still no CC.
Gonna keep close eye on it, ‘ cause I’m not thrilled at upping the SWG much higher. Prob dose it with a little bleach if I leave for a few days. Thanks for all your input.

There is nothing wrong with running a cell at 100%. They all run at 100%! At 50%, it runs for 30 minutes on, and 30 minutes off. Some people, because of the cost of running a big pump, only run 4-6 hours a day. Those with SWGs need to run at 100% to produce enough chlorine.

You may wish to shut down your pump on the weekend and remove the SWG cell and see if it is clogged, dirty or crusted. If it is, clean it out with a garden hose and hose pressure. If you can't get the dirt or crust off, you may need to acid clean the cell. Just a thought.

I recently had to "up" my setting since we are getting a LOT more sun since mid July. However....knowing how MY pool works, and I'm not far away, correcting for the pool size difference, I think you were running the FC ppm a little low and not generating enough chlorine a day. I have a full sun pool, I am running about 70 ppm CYA and I need to add about 2.5 ppm FC a day to keep it up. Your SWG is similar output to mine. For yours to produce 2.5 ppm/day at 6 hours run time, the setting would need to be ~88%. At 8 hours run time, ~66% should be OK.

By September, the sun will be less and we can reduce the settings...

 

[nabril15]

I run my pump low speed 20 hours a day and a high speed 4 hours a day (6-8A and 4-6PM), for the skimmers. My SWG for 25K gal pool is 38%.

hey red-bearded one.
In dealing with a similar issue to the one from this post, I came across your comment above, and I ask why you separate the 8 hours of high speed into 2 slots of 4 hours. Is there a specific reason for doing that way versus running the 8 hours straight?

 

[red-beard]

I run 4 hours a day on highspeed, split into 2 slots of 2 hours each. It is so I have skimming in the morning and skimming in the afternoon. They are set to clean the surface just before times I am likely to swim (around 8AM and after 6PM).