Total Alkalinity headache!

[Paisleyface]

Hi there, this is my first time posting a msg on here, so hope I am going about all this in the correct manner... I have a problem with total alkalinity in my pool. The total alkalinity reading is 200+ The pH is 7.4, and I presume due to the TAK reading I am getting nothing on the Free/Total Chlorine reading. Any advice would be very greatly appreciated. Yours in desperation..

[Baz]

Welcome to the forum Paisleyface.

I would more concerned about the lack of the Chlorine reading and at this stage do not worry about total alkalinity. I would start adding Choc Chlorine until you get a correct reading, this is essential for safe swimming.

Baz

[Paisleyface]

Hi Baz, Many thanks for your prompt response and advice. This is my first season without having people taking care of the pool for me and hence my next question may misguided, but I have read sooo many articles about pools over the last week that I am more confused than ever: I read that as the Total Alkalinity is so high, that is not possible to take a proper Cholrine reading... therefore I am worried about putting in Choc Chlorine as this is adding more alkaline to the pool?? Thanks in advance for your patience with my silly questions! Paisleyface

[Stu-le-brew]

Hi Paisleyface and welcome

I can still remember (five years ago now!!) my first problems with the pool (it

went very green three days after moving in), spent many hours researching on

the net to get to where I am now with a crystal clear pool which is always very

inviting.

The most important thing IMO is PH it should be 7.2 to

7.6 ish much outside this range the effectiveness of chlorine is reduced

(possibly to zero). The PH at this time of year seems to increase progressively

over a period so you need to keep adjusting the PH down.

When the PH is in range I would recommend shocking

(choc) the water first then continue with normal chlorine blocks. You can use

multifunction blocks '4 in1' or '5 in 1' which have various other chemicals but

should not be necessary. I did use them for the first three years with good

results, but you can end up adding chemicals to treat problems you don’t have

and too much can create other problems.

Over a period of time 10days to two weeks Chlorine

becomes locked and has no effect so you will need to use choc to release it to

become effective again.

Your comment that the 'free/total chlorine reading' is

zero confuses me a little as they are two different readings i.e. high total

chlorine and no free means time to choc - the reverse would indicate you just

did choc.

I don’t know what test kit you use I have just moved to

one that uses test strips to tests for five different readings. Some people recommend

using electronic devices to perform highly accurate tests. Personally I remain

to be convinced that decimal places of accuracy is actually needed

hope this helps you

'bon chance'

[Paisleyface]

Hi there Stu,

Many thanks for being so helpful. I also use the strips test, with the 5 readings on them. My free chlorine reading is now 0.5/1 and my Total Chlorine is 0.5. What should these be at?

When you say "normal chlorine" do you mean the big 'lent' tablets?

Thank you very, very much. P

[Stu-le-brew]

my pleasure,

the max range for free chlorine is anything up to two/three ish any more and you start to smell it and can feel it in the eyes, from memory commercial pools can me much higher 5 plus, but in a commercial pool many people can't be bothered to get out for a pee !!

Yes by normal I mean 'lent' tablets (about 8/9cm diameter)

BTW if you ever start to get a reading of no chlorine when you know there is some, it can indicate an excess of cyanuric acid, which is a stabiliser used to slow usage of chlorine - if this ever happens you either have to dump water (maybe half the volume) or switch to using both chlorine and choc without cyanuric (then dump the water at the end of the season - note there is no other way to remove excess cyanuric)

enough of talking about it time to get in me thinks !!!!

 

[Paisleyface]

I completely agree, just one last question, do I just ignore the Total Alkalinity reading?? You have been a brilliant help thanks, enjoy your swim!

[Stu-le-brew]

I'm getting to the limit of my knowledge and interest

in chemistry, I understand that PH is a scale from 1 to 14 lowest being very acid

and high being very alkaline 7 being neutral. So I think if you get the PH right

then that's it

I am sure there are others more knowledgeable who can add to this

 

I'm off to get wet !!!!

[Poolguy]

Paisleyface

Your total alkalinity reading of 200+ is fine and within the normal range  80-300ppm ( you could have read this already as ther are many recent threads on the subject)

The only time you need to take action is if it drops below 80ppm in which case add bicarbonate of soda. Just a note that Chlorine has nothing to do with and will not affect the Total alkalinity - its more likely to be lowered by rainfall, adding large amounts of pH moins, or other environmental contaminenets.

pH seems OK but 7.2 is the optimum.

I am more concerned about the level of stabilizer (cyanuric acid) as you said that your Total Chlor is 0.5 and your free chor is 0.5 indicating that you have no cyanuric acid in the  water.

That would seem strange if you have been using gallets or choc treatment as they are both laden with nearly 40% Cyanuric.

If you can measure that and post then I can advise you on the next step. Certainly though the Chlor readings are too low and should be 1.5-2ppm for this time of year in an unheated private pool.

Andrew