Recommended Chemical levels VS CSI

MickyT

Active member
Hi Folks,
Well done on putting together great website and support for those who have worked out the evils of pool shops. Thank you from “Down Under”. I have a quick question but thought it would be impolite to jump right in without an intro and background, so this is my chance (and promise to be my only time) to waffle on a little. :)

Adhering to the rules of “Happy Wife, Happy Life”, I have recently installed a pool which finally today, I can take possession away from the concrete trades and landscapers who have left me a dusty crud filled pool, which to the best of my ability, I have managed to keep the water reasonably clean with test strips, DPD Tablets and some pool shop tests.

Having been a pool owner some 12 odd years ago, I had sworn off them for life!! Experience with water balance etc was a nightmare being guided by a wolf in lambs clothes, my local pool shop salesman.

But when the wife has had enough, the rule above applies. As it turns out, our summer has been one of the worst ever and probably the worst time to put in a pool (depending which way you look at it). As I sit here in 41c degrees with a low level of concern and stress from suffering through one of our worst droughts and monitoring our bush fire evacuation systems, preparing our bushfire plan as the region burns around, the fact is. (With slight guilt) I still need to turn my thoughts to pool managment, as this giant hole in my backyard is not going away anytime soon, unless of course the worst happens and fires make it to my town.

As I am now older and wiser than I once was, after the 3rd test at the pool shop, I thought “there must be an easier way”, so after consulting my best friend and Doctor (Google), I found you guys/gals and I must say I am impressed with the great spirit of this forum.
All I can say is thank goodness that I didn’t drain my water because my TDS was above recommended levels and that I didn’t ignore Calcium Hardness because it was deemed NOT necessary to test.

So for the last few weeks I have been lurking, reading and learning. The majority of questions that came up had already been answered and I now have a good understanding of what I need to do and where my levels need to be.

So what has come up, which I haven’t been able to find an answer to is the relationship of correct water balance vs the CSI.
So, these are the numbers I am looking to get my pool to from recommendations from you good folk:
FC: 4 - 5ppm
PH: 7.2
TA: 80
CYA: 70
SALT: 4000
CH: 220

When I add these into the CSI on pool math, I get (recall) somewhere around the -0.73 mark.

Should I be trying for good balance or CSI under -0.3??

Thank you in advance for your response and thank you for allowing me to waffle on for my 1st post. I’m probably more stressed than I realise due to our current fire preparedness, so apologies. It won’t happen again.

Hopefully my signature info works which has my pool details.

My first offical test today, numbers are currently:
FC: 3
CC: .5
PH: 7.8
TA: 125
CYA: 50
CH: 100
Salt : Not tested (pool shop 2 weeks ago 4540)

The only other point is our fill water comes from rain water in concrete tank, which is why, I presume, my TDS (from pool shop) is 7025.

Regards
 
Hi and welcome to TFP! What a wonderful write up! I like your style! :hug:

Water temps play a large part in the CSI. Play with the numbers in pool math and see how each one impacts your levels. Pretend you pH is x and your TA is y, ect and see what each one does. You will find what works best for your pool and water source over time. It will take some time and tweaking so make sure to keep very good notes.

Kim:kim:
 
Note that you have a fiberglass pool. Low CSI can cause problems in plaster pools etching the plaster.

High CSI can cause scaling but only with high CH levels which you don’t have.

So keep your water chemistry within recommended levels and don’t concern yourself with CSI.
 
Micky,

Most SWCG pools like there pH to be about 7.8.. When I plug 7.8 into your first batch of numbers, the CSI drops to -.2... Just about perfect....

Look at your second set of numbers, your CSI is about -.25...

Thanks,

Jim R.
 
Welcome Micky! :wave: I would also recommend watching your FC level closely. As you probably know, your CYA is slightly low for a salt pool (I believe you plan to increase to 70), so the SWG may be working a bit harder at the moment to keep-up with the chlorine demand. And with all the debris in the air locally, it may be even more important to keep the FC a bit stronger as it battles organics settling-down onto your water. Other than that, nice post. Have a great weekend. Cheers! :cheers:
 
Hi Folks,
Thank you all for your response and glad I didn't lose you all in my preamble.

Duraleigh: I haven't actually tested my tank water but would presume yes, as that is where we filled from. However, LOTS of dust and debris from dust storms and dead dusty backyard with lots of trades persons and tile cutting near by. Living in a dust bowl and air quality low with smoke at high PPM from bushfires.

KimKats: Thank you - WoW, yes I did play with the numbers again and yes, numbers are like a good party - swinging. Originally I was only playing with numbers from the TFP recommended levels for FG pool, SWG etc. Is it OK to go outside those numbers? According to ("Ostrayan") industry standards, the numbers vary from TFP and if I stretch to some of those figures, I get good CSI. I didn't realise the impact of temperature, we are currently in an official heatwave with another 41c day, but we are due to drop back to 27 - 30 next week which is the norm. My pool is 31c currently with no assistance. Under normal circumstances, the water heater is set at 27c. With that considered - presuming CSI is the more important number:
If I alter my numbers to below, is this OK?
(Wait, I gotta switch between screens)
PH: 7.6
TA: 110
CH: 220
CYA: 70
TEMP: 27c
Salt: 4500

CSI = -0.26

Hang on!!! This is doing my head in. Actually, if I flip my PH to 7.8 and TA to 80, I actually get -0.25. Ahhh and I just added acid to get my PH down to 7.4. I thought I read somewhere that FG pools should have a lower PH of 7.0 - 7.4 (ideally). That may not have necessarily been TFP advice.
PH is sensitive...

Over the longer term, what is the easier level to control? PH or TA?

AJW22: Thanks, I guess that was the main issue. I've read so much, but if I recall correctly, I think there was mention that Gelcoats can have calcium in them, so I am STILL a bit confused as to whether not worry about CH due to FG or still (at least) bring it to 220ppm. I am at 100 and have a bucket load of Cal Chloride ready to go in to raise to 220. Not sure now....

Jimrahbe: Thanks for that! Explains why acid has been my main additive since water went in. Keeps going toward 8 and I keep adjusting to low 7's as per industry standards over here. Cheers.

Texas Splash: Thanks also, yes my chlorine is jumping a little as I learn the output of SWG and yes, I need to get my CYA up. It's taken me about 2 weeks to lose the fear about raising my CYA due to all the worlds information re CYA, including our own governments response to it with Australian Standards advising to NOT exceed 50ppm. However, I am now convinced from TFP and also this article was interesting for all you TFP chemical geeks (who have obviously already worked it out) but it is an interesting read for any AUSTRALIAN viewer which supports TFP stance. Cyanuric Acid - Debunking the 'Chlorine Lock' Myth

Regarding my SWG. It is clearly is well overpowered for my pool. Astral VX25, it only has a 1 - 8 rating for chlorine output. At the moment, (on the 2 days I have been able to try it) on level 5 without pool cover in our stinking hot sun all day, 50 cya, with two swimmers in/out, it is holding 4-5 ppm FC running on low speed for 8 - 10 hrs. With cover on and cover off for a quick swim, level 2 for 6 hours is maintaining 3 - 4 ppm. But this has been monitoring between trades people and I haven't had full control as yet. On level 8 for 24 hours, it gets high (super red with DPD tablet) and pool store reading had it at 10ppm.

OK, so I have done it again, banged on a bit but at least its all about POOL.

So the question that I am not clear on:
Fibreglass Pool with Gel Coat and SWG : Bi-Luminite Technology for Brilliant Pool Colours by Compass
Do I raise my CH to 220 or is 100 acceptable and work around that? Actually - I've answered it myself!! I just went back to Pool Math and CSI works better with 220 CH.

If you're super bored, as a newbie, could someone just double check my figures, Please?

This is what I will aim for:
PH: 7.8 (This scares me - it seems high)
TA: 80
CH: 220
CYA: 70
Temp: 27c
Salt: 4500
CSI = -0.25

OR Slightly raise my PH to 100 (above TFP recommendation) to get CSI = -0.12

Now I'm dizzy..

Thanks folks...
 
Micky,

I suggest that you not try to control TA as long as your pH is somewhat stable.. I only adjust my TA if it goes below 50 or I can't keep my CSI in range. In my mind, TA is the last thing to adjust.

Thanks,

Jim R.
 
pH of 7.8 is not “high”. Higher pH becomes more alkaline and does not cause problems beyond scale.

Low pH below 7.0 becomes acidic and can damage equipment and surfaces. Low pH is what should scare you.

As I said in my prior post, with a fiberglass pool there is no reason to adjust chemical levels just for CSI.
 
Micky, a few things I've learned as a FG owner here in the states:
- Today's FG pools do not use any calcium-based product in the shell, so we don't have erosion to worry about if the CH gets low (or low CSI). But we do require some CH generally to protect from staining. If your CH was to remain at 100, you should be fine, but I wouldn't let it get any lower.
- FB companies in the states all proclaim the same CH range of about 220 - 400 (give or take a few). That's a generic range that they levy on owners, just like an FC of 3-5, or TA of 125-150, etc. They also say to do a "super chlorination" weekly which we now know is not required. Just very generic, antiquated industry standards used a a blanket statement for owners. But we know better with accurate home testing and TFP experience.
- Your next to last sentence you mentioned "pH to 100", but I suspect you meant TA. But a TA of 80 should be fine, and if your pH is fairly stable, I'd leave it alone.

Today's gelcoats are quite resilient, and there seems to be no evidence that a low CSI (aggressive water) will impact a gelcoat, so I wouldn't worry too much about the CSI or splitting hairs with exact numbers. Just try to maintain the TFP ranges and that should work fine.
 

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Thanks for all your input. I’m working out that whilst CSI is a great tool and guide, trying to balance it all out for “perfect” results is not for the faint hearted.. I’m stunned by the effect of temperature alone, so now realise that, particularly where I live, the difference between daytime and night time alone will cause CSI to vary quite significantly.

I guess for me, and presumably a lot of newbies, the fear of it all comes from industry. My Gel coat comes with a lifetime warranty. Read the Clauses and the fine print goes on about maintaining chemistry, pool shop records etc. My “authorisedl” dealer and pool shop are the people we (TFP freaks) want to avoid. It’s where the fear of running 7.8 ph and 80 TA comes from. According to my pool shop that’s too high and low respectively, but I know this is industry BS. Whether it is enough to void my warranty, who knows... Anyway, I digress... I”m sticking with the advice here.

Considering, I’ve jumped the gun and already got a 4kg tub of Calcium Chloride, I will throw it in. That will bring the CH up to just over 200 and I’ll leave it at that for now. Overall, it has positive effect on CSI, so considering I already have it, it’s going in.

Today, I am topping up water level, cleaning as much dust out as I can and by Monday, we should be back to normal daytime ambient temps, I will look to get PH, TA, CYA and FC to suggested TFP levels and see how it all happily plays in my environment.

I’ll start fine tuning from there and see how I go.

Thanks all for your time and input thus far.
 
Micky,

It is almost a forgone fact, that no matter how you maintain your pool, the warranty was written to make sure any damage can be blamed on you. Lifetime warranties are usually worthless in the real world. Unless you can prove it was some kind of manufacturing defect, then it has to be your fault... :mrgreen:

Thanks,

Jim R.
 
Some pools have extraneous issues such as high CH fill water for example. Or a previous problem with scale etc. So for those pools CSI monitoring may be more useful then most other pools.
Otherwise most of us don't need to worry ourselves about it if we manage to keep our pool somewhat stable and within the range of chemistry levels that protect our pool's surface and the water is in good shape.

Maddie :flower:
 
Micky,
First welcome to another "down under" member and not that far up the road :)

General comment: CSI seems to drive many forum members insane with them chasing a number and trying to keep it precise.
There was an older post that was written by one of the gurus (nope can't find it) that really stated it was a great guide and should be observed over time for trends rather then be obsessed about on a daily basis. This is even more so with fibreglass and vinyl liner pools.
As you have observed that with the lower values of TA/CH that is more common in Aust that PH and temp can really swing the numbers up and down quite a bit.

CH will climb all by itself over time as you add water due to evaporation, mines gone from an initial fill level of 125 to be now 225 12 months later.

Remember that all the TFP levels are actually ranges and honestly if it's in the range it's likely good
 
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Cheers everyone,

As a newbie, I think you can definitely get too deeply engrossed in the numbers... I hope to find my groove shortly and relax a little. I'm getting close to target numbers and the pool water looks fantastic, it seems to release endorphins :ROFLMAO:

The new problem with all this, as the only fresh water source I have access to is our concrete water tank, collecting rain water from house roof, I'm now thinking about how CH affects the tank. Plain concrete holding 120K litres of water, I know it is definitely leaching lime. :unsure:... It's our only drinking water and it hasn't killed me yet, so good sign!

And, I can't wait until my stirrer gets here. I think it is on a slow boat from China - literally.. Why we can't buy this stuff in Aus amazes me... And what is it with USPS and delivering to Aus? Seems like it is voodoo and you pay the hefty price..

Take care all and thanks..
 
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Cheers everyone,

As a newbie, I think you can definitely get too deeply engrossed in the numbers... I hope to find my groove shortly and relax a little. I'm getting close to target numbers and the pool water looks fantastic, it seems to release endorphins :ROFLMAO:

The new problem with all this, as the only fresh water source I have access to is our concrete water tank, collecting rain water from house roof, I'm now thinking about how CH affects the tank. Plain concrete holding 120K litres of water, I know it is definitely leaching lime. :unsure:... It's our only drinking water and it hasn't killed me yet, so good sign!

And, I can't wait until my stirrer gets here. I think it is on a slow boat from China - literally.. Why we can't buy this stuff in Aus amazes me... And what is it with USPS and delivering to Aus? Seems like it is voodoo and you pay the hefty price..

Take care all and thanks..
Not so sure it's "plain" concrete per se, can't find anything quickly on concrete mixtures used for water tanks but considering just about every large reservoir used in town water distribution is concrete based i'd be far more concerned about what comes off the roof with the rain than what leeches out of the concrete
 
Not so sure it's "plain" concrete per se, can't find anything quickly on concrete mixtures used for water tanks but considering just about every large reservoir used in town water distribution is concrete based i'd be far more concerned about what comes off the roof with the rain than what leeches out of the concrete

Ahhh yeah, thanks for that thought :sick:. For about 5 years I never worried about it, even my GP said it doesn't hurt to consume some organisms, apparently keeps the immune system active and strong. I have good gutter guard and sealed system so no dead rodents, maybe a bit of decomposing leaf litter, bug detritus and bird poo I guess. However, when my sister visited once and she is super paranoid about life and wouldn't drink water without boiling it :rolleyes:, I ended up fitting a pretty good inline filter on one tap for drinking. I also have a manually activated rainwater diverter which I am pretty reliable for opening prior to rains, when rain hasn't been seen for a while, then shutting after a bit of flow (like this weekend hopefully). There is also a good document online from our Dept of Health talking about concrete tanks and apparently they are quite good. They work on ph 6.5 - 8.5 being acceptable and if higher, still ok and has no implications to health but may affect dishwasher etc (scale). I decided to measure my water this morning. It has a ph 8.5/ TA 60/ CH 100. Water in tank estimated at about 15c temp. Came out with a CSI of 0.15. I'm ok with that. Now back to POOLS.... :oops:
 
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I grew up initially on farms and didn't experience town water till i was around 10, even then the parents installed a rain water tank (Galvanised) for drinking water as they hated the taste of the town water. We never had those fancy rain water divert gizmos :) etc and i can remember painting the metal roofing more than once with special paint both we never worried about the first flush off the roof .... Those measurements are pretty good and at least you know the impact on chem levels when topping your pool up

So back to pools, what are the current levels?
 
Yeah I hear ya, I grew up in Kalgoorlie WA, drank the water that was in the old corrie tank!! My diverter is nothing flash, just a Y piece that has a screw on end, hence the "manually" operated.

My pool is good, I just saw your dust post from last week, I WISH I only had that much dust :ROFLMAO:!!! And, contrary to what I thought, I still can't quite deal with it as I've still got tradies here cleaning up the last of the job on the deck. I thought they were done with the deck, but still some minor bits.... My backyard is destroyed, just a massive fine dust bowl and you are aware of the wind we have been seeing - Hoping this forecast rain comes this weekend, settles the dust and lets hope it's a drought breaker!

My water is really clear, other than fine dust that continues to settle on the bottom. It's not clouding the water which is good. When I can get fully onto the deck, I will brush it all into the floor drain and the filter will need a clean for sure. I'm not stressing about the numbers now as I have read pretty much every post on this forum and quite relaxed about it.

I did a full test on Monday morning prior to pumps coming on - had about 2 hours of sun on it already but I do have a solar cover:
FC: 2
CC: 0
PH: 7.8
TA: 100
CH: 175
CYA: 50
Temp: 26c

I stuffed the salt test up, but confident between 4000 - 5200.

CSI -.23
*8 That was the Monday after the big weekend of 40+ temps, so hoping that may have been why FC slightly low.

I'm still working out my SWG settings, I had it on 4 (scale 1 - 8) and the pump ran for 5 hours. At 1730hrs, pump had been off for about an hour, FC was 3.5ppm. Cover is on and no one swimming currently.

I couldn't get to it this morning to check overnight.. I'm not doing too much at the moment with the numbers until I can get full access to the deck. Pool cover is on, but roller can't be fitted until silicone under tiles/pool edge has cured properly. But I'm happy whilst not the 100% recommended levels, it's in an OK target range and water clarity is good, dust is another story. In Floor cleaner is getting about 70% I estimate, the last 30% will need brush assistance. The in floor cleaner is great for circulation though and I think that is helping greatly.

I hope to get the cover off this weekend, let it breath, do another full test and fine tune it to TFP recommended levels. My only other issue is I have no stock of any chemicals, other than ph increaser initially given to me by pool shop, which I don't anticipate ever needing and the closest place for acid and pool chems for me is a 65km round trip, so I need to work out what to stock and what I need small bits of: ie stabiliser..

AusPhil, where do you get your acid and other chems from?

Cheers
 
I just got out onto the deck and grabbed a quick test sample. Pump has been on about 3 hours, full sun , cover on:
FC: 3.5ppm
ph: 7.6 - 7.8

Admittedly, I am having a bit if a struggle reading the ph. I'm not colour blind, I just find my sample is like a gloss colour and the test colour code is a satin/flat colour. I throws me off a bit.
 

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