Preparing for SWCG

My PB is finally going to install my SWCG (Aqua Rite) tomorrow - at least that's what he says. My 17,000 IG, PebbleSheen pool is now just over a month old. I've been following this forum's advice and thanks to all, plus Ben's test kit, have a nice clear pool.:D

Entire pool is in full sun throughout the day from at least 9 to about 5, then parts in shade. Lower than average bather load; Calcium Hypo used for chlorine until my calcium hits a good level. Have been keeping free chlorine in the 4-6 range for the last week (finally got the hang of this - maybe??)

I know the SWCG mfr says 60-80ppm CYA and that 80 is preferred. I also know there are those on this forum who are operating nicely with a lower CYA. Currently, my CYA is lower than "preferred." Can I give it a go with the SWCG with my current numbers? If my chlorine level currently drops about 2.5 during the day in the sun, what is my risk in running with a lower CYA with the SWCG? I'd like to keep my chlorine as effective as possible.

Anything that jumps out at you that I need to watch for with the startup of the SWCG with my numbers where they are?

This AM's readings:
Water temps 82 in AM to 86+ in PM, air temps will be over 100 this week, so water temps will be close to 90 in PM
pH 7.5+
FC 7.0
CC 0
TA 90
CH 190 (had tested 200 last 2 days)
CYA 25-30 (Ben's test) OR 30-35 (Taylor test)
Salt 600 (must be residual from bleach used prior to CalHypo, confirmed result with 2nd test, fill water stays orange/red with 1st drop)

I'm thinking of pulling my pH down a bit tonight. But what do you think about adding any more stabilizer?

Also, if residual bleach can add so much salt, would I be better off aiming for the lower amount of recommended salt, in case I would need to use bleach in the pool later this season?

Lots of questions, I know. Thanks for your patience, input and opinions.
Sandy

Quote:

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Originally Posted by dawndenise

My PB is finally going to install my SWCG (Aqua Rite) tomorrow - at least that's what he says. My 17,000 IG, PebbleSheen pool is now just over a month old. I've been following this forum's advice and thanks to all, plus Ben's test kit, have a nice clear pool.:D

Entire pool is in full sun throughout the day from at least 9 to about 5, then parts in shade. Lower than average bather load; Calcium Hypo used for chlorine until my calcium hits a good level. Have been keeping free chlorine in the 4-6 range for the last week (finally got the hang of this - maybe??)

I know the SWCG mfr says 60-80ppm CYA and that 80 is preferred. I also know there are those on this forum who are operating nicely with a lower CYA. Currently, my CYA is lower than "preferred." Can I give it a go with the SWCG with my current numbers? If my chlorine level currently drops about 2.5 during the day in the sun, what is my risk in running with a lower CYA with the SWCG? I'd like to keep my chlorine as effective as possible.

I can understand your concerns regarding using lower CYA values. But you haveto remember, and this has been mentioned several times in this forum, that keeping the CYA up to at least 60 ppm helps to maintain the chlorine produced in the cell at high concentrations to be available throughout the body of the pool. You can try lower values, but that is dependent on bather load, sun hours producing evaporation and ultraviolt ray degradation.

Anything that jumps out at you that I need to watch for with the startup of the SWCG with my numbers where they are?

This AM's readings:
Water temps 82 in AM to 86+ in PM, air temps will be over 100 this week, so water temps will be close to 90 in PM
pH 7.5+
FC 7.0
CC 0
TA 90
CH 190 (had tested 200 last 2 days)
CYA 25-30 (Ben's test) OR 30-35 (Taylor test)
Salt 600 (must be residual from bleach used prior to CalHypo, confirmed result with 2nd test, fill water stays orange/red with 1st drop)

I'm thinking of pulling my pH down a bit tonight. But what do you think about adding any more stabilizer?

Bringing the pH down and holding 7.2 - 7.6 will help in maximising chlorine production, and so will the extra CYA.

Also, if residual bleach can add so much salt, would I be better off aiming for the lower amount of recommended salt, in case I would need to use bleach in the pool later this season?

You will need to test for the salt level before you add salt for the SWCG, so you are not adding too much. Once you get familiar with the SWCG operation, this point well be mute. Operating with a higher than normal level helps to increase chlorine production.

There is a post regarding SWCG operation in this forum, which has not yet been made a "sticky" which should help you.

Lots of questions, I know. Thanks for your patience, input and opinions.
Sandy

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Hope this helps.

Pat

Sandy,

I have an Aqualogic controller with SWCG. Last month my CYA was 30 ppm with chlorine at 2 ppm with no difficulties. However, as Pat and others maintain, higher CYA improves chlorine production so I decided to raise mine just to see if it was true.

First I raised it to 50 ppm but I did not see any rise in my residual chlorine, still 2 ppm. Then I raised it to 70 ppm and I still did not see a rise in my residual chlorine, still 2 ppm. However, during this time, I did not have a heavy bather load so I am not sure if that would have made a difference or not. So for me, running at a higher CYA did not improve chlorine production and I cannot see any other benefit from doing so.

Anyway, I told this story so perhaps it might help in your decision. Just remember, it is much easier to raise CYA then lower it.

Pat and Mark,
Thanks for your input.

Pat...I have already read that wonderful soon-to-be sticky and even printed it out for reference. I think it's indispensible and wonderful of you to have gone through all the trouble to reconstruct it for all of us. I don't claim to know everything there, obviously, but I have referred to it more than once :) and will probably continue to do so.

Mark...interesting results!! I guess I'll have to mull this one over. Thanks for the "counterpoint."

Sandy

I also have an Aqualogic and have had exactly the opposite results. I had a leak in my pool so my CYA level was dropping and I found that as soon as my CYA dropped to about 50 I had to crank the output on my cell up to mantain the 3 ppm FC in my pool and the 4-5 ppm FC in my spa. This happened to me twice so it was a repeated effect. Once I bumped the CYA up to about 70-80 ppm my FC levels rose and I had to back off on the output. I currently run my pool at 8% and my spa at 4%. When the CYA levels were lower I has the pool at 20% and the spa at 8%.

Waterbear...just curious but how long are you running your pump daily?

8 hours in my pool broken up into 5 hours during the day and 3 in the evenng and 1.5 hours in the spa.

I had same concern. I was running AutoPilot on level 2 at about 20-25% with CYA of 40. I am starting to raise my CYA SLOWLY(you can always add, but have to drain pool to decrease) by filling a kneehigh with stabilizer and letting it dissolve in the skimmer. I have it up to 50 now and can run my AutoPilot on level 1 at 30 percent and have a FC of 4 and CC of 0 immediately AFTER big pool parties and the purifier is usually off when I look at the panel so I am happy where it is right now(though I do have some CYA still dissolving as I write this).
I run my filter for a few hours after the pool is put to bed for the night so the SWG can do it's thing with no added bather load or sun to interfere.

Thanks for all the input. My CYA tested between 30 and 40 with Ben's test kit this AM. I'm out of CYA, so will trot off to the store to have some more on hand. I don't think I'll shoot for 80ppm, even though it's preferred, but I am leaning toward nudging it up a bit, as my chlorine is taxed quite a bit each day from the sun. But I'm still weighing everyone's opinions and deciding where I want my CYA initially.

PB is here working, but I haven't seen my SWCG as yet (panel is already installed, but not the actual cell). It's threatening to storm, so that installation may not be part of anyone's plans today. :(