adjusting the SWCG - what's "normal"

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The only thing missing from that kit is the FAS-DPD test. If you add it, you will have the equivalent to the K-2006 which is one of them that we recommend.

It is best to store them inside in a dark closet. Being outside in the heat (or cold for that matter) I think can mess up some of the reagents.
 
jblizzle said:
How do you have 240 post and not know that ;)
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So, in my defense... The guy who helped spec our pool put the test kit in the plumbing materials order along with other startup stuff (a few cases of acid, salt, etc) without asking us. We were basically trusting him to order what we needed and I think he did a good job. I did not start reading much about chemistry here until I had water in the pool... at which point I remember being worried we got the wrong kit - but I had checked and it was a Taylor twothousandsomething which seemed roughly right, so I promptly forgot.

So now I guess I see a difference between DPD and FAS-DPD, eg 2005 or 2006...
 
When the filter gets dirty, the pressure at the VRV will drop and in some cases, will start to draw air if the pressure drops too mouch. What was the clean filter pressure? Also, how high are the panels?
 
We recommend cleaning the filter when the pressure goes up 20-25% of the clean pressure. If you started a 8psi, you are now 50% over. If you started at 10psi, you are now 20% over.

Either way it is time to clean the filter, which may increase the flow enough to eliminate your air problem.
 
With a clean filter at 8 PSI, you had about 3 PSI of margin (~5 PSI static head rise) which could easily get used up with the head loss between the filter and VRV. With an additional 4 PSI rise due to a dirty filter, you are taking away that margin plus some so it isn't surprising that the VRV is drawing air. This really isn't a design flaw or a problem with the system but a limitation that exists when running solar at lower RPMs. Either clean the filter more often or run at higher RPMs.

However, if you really want to run at lower speeds, the best thing to do is to drop the VRV to a lower elevation on the supply side of the plumbing (i.e. a few feet above the pad). This will allow you run at lower speeds even with a dirty filter (up to a point).
 
So over night the FC went from 3-5 to 0, so that would indicate something is growing?
So this morning I am trying our (first ever) shock. I used the pool calculator and added the indicated amount of liquid chlorine and I also put the SWCG at 100% duty cycle.

Since we've had no time to order the FAS-DPD... the only instrumentation I've got for this is the DPD test. Is there a way to confirm I've got a FC level of 24? eg - is it worth diluting the sample by say, 50% and doubling the reading? Or are we just flying blind here?

Thanks... as I learn by doing... ...
 
Your first dose of chlorine will be the only dose that you will know what your chlorine level is at, but you will not know how long it even stays at that level. Without the FAS-DPD test you will only be to estimate your FC level and if you let the FC drop to a level that you can accurately read it, then you will have lost ground to the algae. If you overdose the FC you can do some damage to your equipment. Also, to pass the OCLT test, you need to be able to read your FC accurately enough to say everything is definitely killed off. I highly suggest ordering the FAS-DPD test from Dave today and it will arrive soon.
 

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Re: adjusting the SWCG - what's "normal"

You can try diluting with distilled water, but loose accuracy and it is certainly not accurate enough to differentiate 0.5ppm difference. Although could help estimate dosing until the FAS-DPD arrives.

Posted from my Droid with Tapatalk ... sorry if my response is short ;)
 
davelinde said:
I also put the SWCG at 100% duty cycle.
Click to expand...
We recommend turning off the swg during the shocking process and just use bleach/liquid chlorine to chlorinate. 2 reasons...1. Saves some swg cell life...2. With the swg off you have a better idea of how the shocking process is progressing, especially overnight.
 
Test kit arrived today, nice!

FC 16
CC .5

So starting around FC 24 after two days I am losing in excess of 4 ppm/day and generating CC...

I guess the right next step is to add liquid chlorine to get the water to 24ppm again and test for loss tomorrow morning? Much easier with the test kit than guessing...

So the question is... Where did we go wrong with the SWCG? If we had bumped the FC level before the swim party would we have avoided a week of shocking? The test numbers are key because the pool is crystal clear and still has no smell.
 
Re: adjusting the SWCG - what's "normal"

Usually a good idea to add a few ppm of FC before and after a party using bleach.

Posted from my Droid with Tapatalk ... sorry if my response is short ;)
 
jblizzle said:
...time to clean the filter, which may increase the flow enough to eliminate your air problem.
Click to expand...

FYI, we did clean the filter the other day (finally) and the air from the solar stopped - so that's what caused that.
I don't think the air had anything to do with our sudden drop in chlorine.

At least now we know... if the solar starts to bubble, go clean out the filter! convenient indicator.
 
davelinde said:
So I was just re-reading pool school stuff and I realized that we also got an inch of rain which could have impacted my FC too.
And, now reading how to shock I'm wondering how I get something to measure FC levels above 20? Our kit does ranges that top at 10... do I need a better kit or do I just calculate the shock level, dose it and assume?
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aaaack! all those months of posting while in planning and construction stages and no one suggested a decent test kit before!??

I like the TF-100 cause I can get all the tests in larger quantity. Its a nice compact thin kit and I've tweaked the dividers inside the box so that each test's entire contents are all together, and I can just move from section (test) to the next section (test) easily.
I've also splurged a little on the automatic stirrer cause it really does help things go faster and easier. The only other test kit I needed is the salt level test by Taylor, but its used infrequently.

I also use the TF-100 to test my hot tub instead of the strips.
 
YippeeSkippy said:
davelinde said:
...I'm wondering how I get something to measure FC levels above 20? Our kit does ranges that top at 10...
Click to expand...

aaaack! all those months of posting while in planning and construction stages and no one suggested a decent test kit before!??
Click to expand...

Actually... I explained that above, I'd missed the difference between a Taylor two-thousand something and Taylor two-thousand something. For all the advice to "get a good kit" I don't remember reading the details on why one kind of titration differed from others - I remember a lot of "the strips are not reliable" but that's it.

np though - I know now and we seem to have caught it before anything bloomed and made issues. Thanks to those here.
 
Re: adjusting the SWCG - what's

jblizzle said:
Usually a good idea to add a few ppm of FC before and after a party using bleach.
Click to expand...


AAARGH! I missed the "after" part.

So we are going around this for our second lap now and apparently still learning. Last weekend the kiddies were all here and in the pool constantly for two days. I was smarter this time and convinced the boss of our pool service (the wife) to let me drop some extra chlorine in before the extravaganza. I added enough to bump it a couple ppm and DW confirmed to me we are "around 5-10 now" (I bit my tongue wondering why we are back to the old test, but figured that 5-10 was OK).

After the two days of bather load I asked, with no small curiosity, how the numbers looked on the pool. The answer was "perfect, but add some acid" so I did. Yesterday I asked about the pool numbers again and got that annoyed look...

Well, today I was just told that something might be wrong with the SWCG because for no reason the FC dropped from "perfect" to zero some time in the last few days...

I'm thinking that my mistake was not bumping the FC up again after the weekend? I'm wondering if I should hide the DPD reagent to "strongly encourage" more use of the FAS-DPD?

Just a check here... if I'm still missing something. I'm thinking that the swimmer load introduces biological materials in the water, stuff that can reproduce itself? The idea that chlorine only "goes away" for two reasons (sunlight and reaction with stuff in the pool) makes sense. So with the SWCG only set to replenish the loss due to sunlight there is a need to bump the FC when we know other stuff is going into the pool. The numbers "look OK" from a DPD test on day 1 or 2 after the swimmer load because with only ranges measured, the FC is dropping from the high of the range to the low and then into the high of the next range losing a few PPM each day but seeming like the change was only from high (5-10) to good (3-5) as the level is actually plummeting to zero?

With the SWCG only keeping up with sunlight loss and nothing keeping up with other loss am I correct that the loss will accelerate to zero?

The plan at this point will be to raise the FC to target, then do an OCLT to confirm we need to shock. Seems OK?
For the next pool party, I guess we bump the FC before AND after and see what happens?
 

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