Swimming pool again

Good morning
If John Withall or someone can advise please.
My pool chemistry is as follows and I’m not sure if I should alter my alkalinity or not before shocking the pool.

Ph 7.5
TAC 81 mg/l
TH 115 mg/l
Iron is fine
Phosphates 0.688
CYA 2 mg/l

Thanks in advance.


Thank you.
The pool shop have given me a list of things to do but I know John will have the proper answers.

Good morning, passing through to look for the latest travel info, June the 8th it’s ok?

Back to Theresa,
Vinyl/fiberglass pool? if so then that total alkalinity is fine, I run mine around 40ppm and haven’t added pH minus in 2 years. (BIG NOTE!!!) I use eau de javel and NOT galets, using galets will cause a sharp dip in the pH because they are made to support higher 120 ish total alkalinity as required in concrete/plaster and tiled pools.
I would use a phosphate remover and get that figure down, phosphate removers can cloud the water for a while.
You need to increase your CYA to around 30-50ppm so using cheap Dichlor formulated chlorine galets will increase the CYA level, remember what I said above about total alkalinity but at 80ppm you will be fine.

What did the pool shop suggest?

Thanks for your reply.
I used some chlore choc pastilles last night mainly to get my cya up and also increase my chlorine.
The shop recommended I reduce my ph, I didn’t because I thought my alkalinity might drop.
The shop said in two days I should add a chemical to increase alkalinity and also increase my TH as my water is too soft.
I haven’t done anything except add chlore choc.
My water is v. milky, I assume that is the chlorine.
When should I add the phosphate remover?
I will take a sample of water to the shop after lunch for them to test .
Thanks again

The shop talk total nonsense! Nothing wrong with your pH, it will rise when you choc but that’s only temporary as the pH will fall back as the choc chlorine reduces back to the usual level.
If your pool is vinyl or fibreglass then do not adjust the TA or the hardness, neither of these are relevant to these pools. I have customers in the Dordogne who’s water is incredibly soft and nothing bad has happened. (we run slightly higher pH to reduce any issues).
Choc pastilles can cloud the water for a while, cheaper Dichlor galets will increase the CYA faster and provide the chlorine until you can switch to javel.
Phosphate remover should be added following the manufacturers instructions but enerally when choc levels have reduced.
How are the shop testing the water?

The shop have a special machine where they syringe water into a cartridge in a black machine.
I used the choc pastilles yesterday but I think the lack of cya burnt the chlorine off quickly.
Today I have put two chlore lent galettes in the skimmer.
I will get a ph and alkalinity chk. no-one ever told me to increase TH before. So i thought you would say not to bother.

My biggest worry is even with a shock yesterday and two galettes today my free chlorine is still less than one. It is unseasonably hot even for the Dordogne.

That’s a LaMotte Spin test, good machine, my worry over the years has been pool shops using dip strips!

Yes with low CYA your chlorine will disapear in a matter of 3-4hours, of course as they dissolve you’ll maintain some residual chlorine so long as you have more than 0.5ppm overnight you should be OK but your daytime chlorine demand will be much higher.

Maybe keep the pool covered as much as possible?

Thanks again for your help.
Yes we are keeping the pool covered as much as possible.
I tested the free chlorine today with a fas dpd test and it’s just under 2.
The combined chlorine is 2, so all good .
I have 3 chlor lent galettes but will reduce to 2 hopefully after test at pool shop on Monday next. Hoping the cya will be about 30.
I had a swim today for the first time this season.

Hi Teresa,
You said combined chlorine is 2? Did you mean Total chlorine or combined, combined should be 0 or as near as possible.

Sorry. I meant total chlorine.
Free chlorine was definitely just under 2.

Went out for just 1 hour this morning with cover off pool and chlorine has dropped to under 1. The cya must be really low.
I’m going to the pool shop tomorrow to get an accurate chk. We will only take cover off now to swim until cya has built up a bit.

Thanks again for your help.

In ground pool liner.
Hi my liner has just popped out of the rail in two corners and impossible to push back in. It’s 10 yrs old and I can’t get hold of the person who installed it. Does anyone know anyone in the Gers near Nogaro who could put it back in place please.

One thing you could try is to pour some hot water on it, makes it much more pliable and hopefully easier to get back in

It looks to me that the liner is still in place. All I can see is the liner lock trim has popped out, in which case just push it back.

The lock trim has always been a problem and yes I know to push it back in. This time it’s more serious the liner itself has dropped down and needs pushing back in then the lock trim. I have seen it done before elsewhere by heating the liner. Problem in on my own it’s in the deep end 2 5 metres I’m afraid more of it will pop out I need a pro. I think.

Ok thanks for the clarification, not that obvious from the photo.
You’ll need to drain 30-50% of the water to allow sufficient give in the warmed liner. Do not use water hotter than your hand can tolerate. Clip with spring clamps at the start and end of the area to prevent the liner opening up further and work quickly.

The liner lock often pops out because the installer stretches it too much so it gradually shrinks back. By a metre from the pool shop and cut the liner lock and insert the new piece. Make it a metre to the joins and it won’t notice.

Do anyone now where I can get a 5x5 meter pool that is deep at least 190

You can buy kits and build whatever depth you want, liners can be made to fit.

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