Filling New Pool Q's

Interesting, there are no additive type products on their web site. Give them a call if your want, I spoke with them when I was shopping around for equipment and they were very helpful. I suspect it may be a sequestrant to prevent possible staining from the the new water. Something similar was added as part of a startup kit to our pool.

Its a bit late now but I would have been tempted to add bleach from the start of the initial fill and maybe even a floater with tabs To keep on top of any algae from the start.
Yep. I'll buzz them on Monday for a run down of what is in the container. They have been really good when I have spoken to them too. I only guessed it was an algaecide because it really knocked the green tone of the on the head rapidly after addition of the bottles. The water also went cloudy at that time.

I don't think the progress to handover has gone how the pool builder or I would have hoped. Maybe some LC or a floater would have been good in hindsight but no point crying over split milk. I haven't had the right monitoring tools anyway.

I'm sure it will all sort out fairly readily, looking at what the folks in snow areas deal with every year. Just need to make sure the hand over and I are on the same page and he doesn't add anything wild at start up.

Yesterday for comparison. Greener but clearer:

IMG20230421072824.jpg
 
The pencil compaction is done and the handover of the pool should happen before the weekend. I have tried to throw 2ppm of chlorine at it a couple of times a day to try and hold the line a bit. Probably pointless but gives me something to do and the test strips seem to bear some relationship to what Pool Math says should happen which gives a bit of confidence. Looking forward to getting my test kit. Overnight it looks like the pool has gone from chewing up the full 2ppm I have added at bed time to leaving a hint of FC.

I have been having a good scoop around daily and hopefully have the bulk of the bigger organic bits out of the water.

Still a soup but I feel (foolishly?) confident that I have the right tools and information to get things in good order once the filtration is up and running.

IMG20230425081952.jpg
 
Well...we're pumping water! Pool tech wants to get the water cleared up some, so he can see what he is doing when he cleans the sand out the pool. Seems reasonable.

Got some pool literature. 1ppm FC level recommended, 2ppm OK if you have 50-70ppm CYA. Lot's of "You will bleach your Pool and void your warranty" type of stuff for exceeding recommended FC levels and a recommendation to shock the pool fortnightly in summer, monthly in winter plus whenever is needed. Not sure what to make of that approach :/

I can see why a pool store might want you to operate on the bleeding edge in terms of keeping the pool sanitised (ie you have regular stuff ups that necessitate a trip to the pool store) but you would think a PB would want their customer to have a pool that doesn't cause them ongoing management issues. Is there anything to the shell bleaching story? Is there any reading on this issue? Most of the pools on here seem the be plaster finish or liners so maybe the issue is less relevant?
 
Got some pool literature. 1ppm FC level recommended, 2ppm OK if you have 50-70ppm CYA. Lot's of "You will bleach your Pool and void your warranty" type of stuff for exceeding recommended FC levels and a recommendation to shock the pool fortnightly in summer, monthly in winter plus whenever is needed. Not sure what to make of that approach :/

Is this just general literature? What does your pool liner manufacturer specifically state in regards to warranty requirements?

I don't really see the point in maintaining 2ppm and then shocking (with an unspecified FC, far exceeding the 2ppm they told you not to exceed under no circumstances ???) every two weeks to deal with problems you would have avoided by maintaining a constant FC 6 @ CYA 50 or FC 8 @ CYA 70 in the first place?

Your source considers 1 ppm without CYA to be acceptable, but 6ppm with CYA 50 are evil.

Let's put these numbers into perspective:

FC 6 @ CYA 50 is in terms of HOCl and OCl- (which are both oxidisers with potential bleaching effects on materials, but only HOCl acts as a sanitiser) equivalent to FC 0.11 @ CYA 0.

FC 0.64 @ CYA 0 is equivalent to SLAM-FC, e.g. FC 20 @ CYA 50.

FC 1 @ CYA 0 (still acceptable according to your sources) is equivalent to FC 24 @ CYA 50.

Let's say someone shocks every 2 weeks with FC 10 @ CYA 0. This would be equivalent to FC 55 @ CYA 50.

But if you maintained your pool at FC 6 @ CYA 50 or FC 8 @ CYA 70, this would destroy your liner and void your warranty? Convenient for the manufacturer, but without any scientific reasoning.

Just saying...
 
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...

Let's put these numbers into perspective:

FC 6 @ CYA 50 is in terms of HOCl and OCl- (which are both oxidisers with potential bleeching effects on materials, but only HOCl acts as a sanitiser) equivalent to FC 0.11 @ CYA 0.

...

But if you maintained your pool at FC 6 @ CYA 50 or FC 8 @ CYA 70, this would destroy your liner and void your warranty? Convenient for the manufacturer, but without any scientific reasoning.

Just saying...

Bolded the relevant bit I think.

I guess the only issue is if the chlorinated
 isocyanurate
 compounds could in any way produce a bleaching/damaging effect unrelated to oxidising potential( which they have been shown to not possess)

TFP principles make a lot of sense to me. It's bizarre the industry seems so resistant to the concept. It's amazing how much power "It's always been done this way" has and how science is so easily is sidelined in the face of belief.

...but then you have an investment totaling a scary number and you get a bit scared going against the grain :eek:
 
This is on swim suits, not on liners, but gives a good idea about chlorine damaging materials with and without CYA:

I don't have actual data on that, but anecdotal evidence supported by chemical theory. My wife swims in an indoor commercial pool over the winter 3-4 times a week that has had 1-2 ppm FC with no CYA in the water and every winter season her swimsuits get worn out where the elastic gets shot and the fabric gets thinner, basically having her need to get new swimsuits for each winter season. In our own outdoor pool with 3-6 ppm FC and 30-40 ppm CYA, her swimsuits have lasted for 9 summer swim seasons swimming almost every day though she now says she is starting to notice wear. The difference in active chlorine level between the two pools is roughly a factor of 10-20 which likely is reason for the difference. The same is true for the flakiness of her skin and frizziness of her hair between the two pools.

Obviously the answer will depend on the actual fabric of the swimsuit and frequency of use, but I'd say that roughly speaking 40 expsoure-hours in 1-2 ppm FC with no CYA is probably when the swimsuit gets too worn out (assuming she was rotating between at least a couple of swimsuits). Remember also that there is physical deterioration from wearing the suit and swimming, not just from chlorine exposure, but the difference in experiences between the two pools shows that the chlorine difference is the major factor. In our own pool with an FC that is around 10% of the CYA level the swimsuits are lasting around 900 exposure-hours or so which is somewhat better than what the chemistry would predict.

A shock level of chlorine where the FC is around 40% of the CYA level is equivalent to 0.6 ppm FC with no CYA so a swimsuit would last around 70-130 hours while at yellow/mustard algae shock level where the FC is around 60% of the CYA level and is equivalent to 1.5 ppm FC with no CYA so would last around 40 hours and be roughly similar to an indoor pool that didn't use CYA.

Note that there is another factor that is dependent on the FC level alone and not on the active chlorine level. Namely, it is the chlorine capacity or reserve to continue to react with the swimsuit after one gets out of the water and such water evaporates. In this situation, a higher FC can lead to more swimsuit wear unless one rinses their swimsuit after they get out of the pool. My wife would normally do that with her suits except on weekends when we would both be using the pool and hang out in the sun after swimming.

FYI: Chem Geek is largely responsible for digging out decades old research to back up empirical findings about higher CYA levels requiring higher FC levels, and quantifying the FC/CYA Levels.

I can only add that you hardly notice the chlorine in our pool, usually maintained around FC 10 @ CYA 80. Our suction cleaner lives happily permanently in the pool for the last 5 years or so.

But in the end, it's up to you.
 
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Home testing is not as bad as you might think. Since you appear to be prepping for a SLAM Process, focus on a good CYA test first so you know what FC (SLAM) level to be at per the FC/CYA Levels. Lower the pH to about 7.2 before increasing the FC and you're off & running in the SLAM Process. As you can see you have lots of encouragement in this thread already, so stick with the advice and you'll be clear in no time.
 
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It's amazing how much power "It's always been done this way" has and how science is so easily is sidelined in the face of belief.
There is certainly that, but also why would they give up the cash cow of doing it the expensive way ? Mismanage....mismanage....mismanage. Drain and fill with new chemicals. Mismanage......mismanage.....mismanage. :roll:
 
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Home testing is not as bad as you might think. Since you appear to be prepping for a SLAM Process, focus on a good CYA test first so you know what FC (SLAM) level to be at per the FC/CYA Levels. Lower the pH to about 7.2 before increasing the FC and you're off & running in the SLAM Process. As you can see you have lots of encouragement in this thread already, so stick with the advice and you'll be clear in no time.

I have to do a bit of lab work, pretty much all titration stuff, in my job from time to time so I'm not too concerned/afraid of the process. It's just having the time to approach it methodically when I'm unfamiliar with the process.

I'm planning to get a solid set of baseline numbers when the pool is handed over. Then make any necessary adjustments and have a crack at the OCLT and see what's what. FC appears to have been holding pretty good the last 2 nights but that is just test strips vs eyeball MkI. The pool consumed a chunk of chlorine today (eyeball MkI 1-2ppm) with the filter running and pretty low UV index so I have to do some monitoring with the right tools to appreciate what is going on.

I'm also still trying to decide where I sit on the chemical sanitation vs mechanical filtration spectrum. I essentially have free electricity during sunlight hours so can turn over more water economically if I believe that has merit.

Probably geeking out a bit but with middle age impending I need to find my lane :ROFLMAO:
 
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Testing seemed easy enough.

Afternoon test:

FC - 0 - No colour response to the addition of detection powder. Test strip FC test also showed 0 FC as an aside.

CC - ? - Can you test for CC if you get no response to the the detection powder? Should you test for CC if your FC is zero - I'm thinking I should have done this step, especially in the absence of FC... I would simply add the chlorine detection drops to the clear sample and see if there is any response, given the titration for FC is from pink to clear. I'll look at that on the next test.

pH - 7.8 or above - The sample remained out of range alkaline so I presume this can only be read as the pH is a minimum of 7.8 and potentially any unknown amount more alkaline. I calibrated the pH meter at work today...should have dragged it home in hindsight. Not sure how to proceed if looking to lower pH target. Presume treat as 7.8pH for muriatic acid addition, add appropriate amount for desired change and observe pH test response, continue to treat as pH7.8 until test comes into detection range. Dose appropriately once in detection range of the pH test?

TA - 100 (or below) - Performed the standard TA test which is advised for TA above 100. Drop number x 25 = TA in ppm. 4 drops to change colour = TA unknown level below 100ppm. I will run a high sensitivity test (TA expected below 100ppm) for this value next time to get an accurate figure. The test strips have been suggesting 80-120ppm to date so I wonder how that will shape up.

CH - 125ppm. Might need to come up a bit? Pool is fibreglass.

Salt - Not tested. I have at least several more days of dosing LC and will cross-reference with the pool tech when he is going to add the start-up salt. Given the test kit only sugggests it has enough reagents for 12 tests I don't think I need to burn one at this point.

Can I pretty much presume the pH, TA and CH of my tap water is in line with these numbers given the only additions to the pool has been LC so far?

Pool manufacturers suggested levels for comparison:

1682679511248.png

TFP ignores TDS or is this accounted for in the Big 5 that TFP tests for?
 
Yes , you can test for CC with FC zero.

Yes, the CCL pH-test maxes out at 7.8, which is a bit annoying. I actually got a Taylor comparator block now for that reason, but mostly use a pH-meter. For dosage, you enter 7.8 as current into PoolMath and then calculate dosage required to lower to 7.6. Run pump for 30 min after adding acid, then retest pH and repeat if required.

For TA I would use the test with a 25ml sample to get 10ppm per drop resolution. You want TA a bit more precise, as it is important to get the acid dosage right, and to get a reasonable CSI value (EDIT: low CSI is not an issue for you, but you don't want CSI too high to avoid scaling, and with a SWG you want a slightly negative CSI to keep the cell clean).

For CH, the test with a 10ml sample and 25ppm resolution per drop is sufficient. I think with a fibreglass pool, that CH should be fine. I wouldn't worry about it now and see how it develops over time. Depending on rain amounts it can rise or drop over time. My CH drops over winter and only slightly rises over summer with fill water replacing evaporation, so that I have to add calcium chloride from time to time. Maybe bring it up to the lower end of the manufacturer's range.

Have you added CYA yet? You want some in the water to have your FC moderated, otherwise you'll have astronomical HOCl each time you add chlorine, but then it burns off in no time. You don't need much over winter, but I'd recommend some

Regarding the manufacturer's levels - they only seem to be "suggested", so there is no implication that warranty requires following them?

The differentiation between FC targets when stabilised vs. unstabilised chlorine is BS. Important is the current level of stabiliser already in the pool, not whether you add a bit of stabiliser with your chlorine. But continued use of stabilised chlorine lets the stabiliser level creep up, requiring ever higher FC following TFP's recommended FC/CYA Levels. I find the recommended FC range a bit too low.

With stabiliser, pH up to 7.8 - even 8 - is OK, and will result in slower pH-rise. The CYA-FC equilibrium chemistry flattens the HOCl's pH despondency, up to 8 or 8.2 is definitely covered by the recommended FC/CYA Levels in regards to sufficient sanitising power.

I'd recommend to stick to the lower TA range. Try to avoid raising TA before hitting TA 50, otherwise you'll just get into a baking soda / acid seesaw. My TA is quite stable in the range 70-90 ppm, I never add Alkalinity increaser (baking soda). I still have a bag from the old days that my wife uses in the garden now.

TDS<1500 is chemically impossible with a SWG, salt is the main constituent of TDS. TDS is meaningless, it's just a sum of everything that's in a pool. If TDS is high because of rocket high CYA, then this is a problem. But to identify this, you test directly for CYA. Important is that your individual water parameters are in range, TDS is pointless. Historically, it used to be an easy to measure indicator in pools that were exclusively chlorinated with trichlor tabs. Once TDS got that high (caused by added chlorine turning into salt and the CYA that comes with the trichlor) it was an indicator that the pool was over-stabilised by then and time for a water exchange to get rid of the CYA.

Follow the salt levels that your SWG is specified for.

Don't obsess over phosphates. But that is something that some manufacturers (especially for SWGs) fuss about the most when it gets to warranty claims, and it won't hurt to follow their advice, as long as you do it based on your own testing (I use the LaMotte Insta test about 1-2 times a year, they are strips that add a reagent to the water and then you compare the water colour with a chart).
 
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Only additions so far are LC. I figure not changing the chemistry too much is beneficial if the handover is done by rote for the district rather than by measurement.

Adding 30ppm of CYA looks like it will have an impact on pH so that will be where I start I think, at the appropriate time.

Appreciate the input!
 
Okey Dokey.

Added 600mL 12,5% LC after last nights readings. approx 1.7ppm FC by pool math but did not restest.

Woke up to:
FC - 1.0ppm (2 drops to clear)
CC - 0.5ppm (1 drop to clear)

TA - 80ppm

Added 720mL 12.5% LC aiming for ~3.5ppm FC

Retest 45mins after addition

FC - 4.0ppm
CC - 0.0ppm

Just to confirm...if I add 30ppm of CYA to the pool TA should rise to 110ppm but I remove my CYA level from the TA number when considering "ideal" levels for the pool?
 
Just to confirm...if I add 30ppm of CYA to the pool TA should rise to 110ppm but I remove my CYA level from the TA number when considering "ideal" levels for the pool?
No. Only a portion of the CYA adds to the TA. And do not adjust the TA. PoolMath does all the proper adjustments with the test data properly entered.
 
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When adding CYA, the TA remains constant. Part of the carbonate alkalinity gets replaced with CYA alkalinity.

CYA alkalinity is still real alkalinity. You only subtract it from TA to get carbonate alkalinity as a measure for the amount of carbonates in the water for CSI calculation purposes. PoolMath does this automatically when entering TA and CYA.
 
OK I tested CYA and got a 0. I have 1kg of CYA adding to the pool now. It's shy of the pool math recommendation for 30ppm but I am supposed to try and sneak up to the desired levels from what I have read here, especially when I have no prior experience with how the pool will respond. I should give this a few days to a week before thinking about retesting CYA level iirc? What do I base my FC target on during this period?

I check the pH impact at that point too? Do I retest TA at this point too - not to adjust but just to reference.

My 4ppm of FC was gonski after 4 hours today under a moderate UV and had 0.5CC again. Hit it with another 850mL of LC and went shopping for the CYA. Pretty sure the FC loss is part UV and part algae related.

Pool tech messaged me about making sure I have the pool topped up to near overflowing before he returns. I am presuming he is intending to vacuum all the sand and muck to waste. Once I have this clean slate I will be able to attack the sanitation with a proper SLAM.
 
The CYA here in Australia comes as a fine powder, not the granules they get in the US.

I put the powder in an old sock (or two) and tie it to a stick. While submerging the sock, I keep kneading it with my hands. Like that the powder stays powdery and doesn't solidify into a huge brick that takes ages to dissolve.

Then you can hang the sock on stick either in front of a return water outlet (with a weight on the stick) and let it dissolve, which might take a few hours

Or, which is what I usually do, pull the sock with the stick a couple of times around the pool. The powder will leave the sock and most will dissolve quickly. Some powder will settle on the bottom. I'll give it a push with the pool brush and it will disappear quickly. Like that, my CYA usually dissolves very quickly.

Then assume that CYA increased to what PoolMath told you it would and dose chlorine for that level.
 
The CYA here in Australia comes as a fine powder, not the granules they get in the US.

I put the powder in an old sock (or two) and tie it to a stick. While submerging the sock, I keep kneading it with my hands. Like that the powder stays powdery and doesn't solidify into a huge brick that takes ages to dissolve.

Then you can hang the sock on stick either in front of a return water outlet (with a weight on the stick) and let it dissolve, which might take a few hours

Or, which is what I usually do, pull the sock with the stick a couple of times around the pool. The powder will leave the sock and most will dissolve quickly. Some powder will settle on the bottom. I'll give it a push with the pool brush and it will disappear quickly. Like that, my CYA usually dissolves very quickly.

Then assume that CYA increased to what PoolMath told you it would and dose chlorine for that level.
Yep...made a brick with the powder but hooked into it and got it all out of the skimmer sock I put it in. Will put a nitrile glove on next time. Clouded the pool nicely so I have the pump running overnight.

Down to bugger all FC again so whacked it with a litre, aiming for 4ppm. Let's see what the morning brings.
 

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