I am struggling to stop our pool going green !?

[Teapot]

As above, 1.7 ltrs should give a shock level of 10ppm. Depending on your CYA level you may need to go higher. Shock level at 40% of CYA level.
So if you have 50ppm of CYA x40%= 20ppm shock level of chlorine.

[flynnboy]

Sorry Teapot I did not realise that you were giving the figures based upon the size of my pool.... I am a newbie at this and mathematically challenged in addition !! You have been a great help and I thank you !

[flynnboy]

Hi Teapot, I hope you are having a good holiday despite the weather ! Can I ask further advice please ! I have used THT powdered shock at the beginning of the week and the pool went milky, which I gather is normal, and is better than green......however, it remains a cloudy milky colour and it is not showing any signs of shifting. The ph appears mormal. Will it clear or is there something else I should do ? Thanks again !

[Teapot]

HTH is calcium hypochlorite, it will make the water even harder and you risk scale formation. Being calcium, it is by nature chalky. There are really good reasons why I said eau de Javel and not just financial.

[flynnboy]

Thanks, I was not ignoring your advice, I simply have not been able to get to a Brico yet and I already had some HTH, didn't think it would be a problem......... hey ho.... this is becoming a full time job and the pump seems to have been going since last Easter when we opened it up, that is how long I have been struggling with it !

[Teapot]

Well it will get a lot easier if you follow Dennis and myself, really have to work hard to start with and really need a good test kit, then you'll wonder why you ever struggled

[flynnboy]

I cannot actually find anything decent here.........I suppose I might have to look inthe UK and have something sent over to me.

[Teapot]

Ok, I can help with that if needed, been sending and supplying test kits in France for 10y. Discuss when I get back to UK next week

[flynnboy]

Ok, thanks Teapot.

[flynnboy]

Hi Teapot, I have been to the Brico and bought 20 ltrs of Eau de Javel, my only concern is that it says on the lable 'Extrait' de Eau de Javel - 9.6% Chlore, is this the right stuff ? If it is I'm chuffed because it was under 13 Euro.

[Denniswiseman]

That's about 10% chlorine. You can use Pool Maths to work out how much to use

[flynnboy]

Thanks, but what I really need to know is, is this the right stuff ?

[flynnboy]

And thanks for the link, which is totally nonsense to me, unfortunately !

[Denniswiseman]

First of all decide what unit to use US Imperial or Metric
Then put your pool volume in
Put the current FC in Now and what you want in Target
Put 10 in the first variable for bleach
Then click calculate and the result is in the Add box
Play with it and test it out

[flynnboy]

If FC is 'Free Chlorine'........ I have no way of calculating that........