We bought a new (to us) house this spring that came with a pool, it is about 70,000 litres (18,500 gallons), vinyl liner, sand filter, gas heater, and so far things have gone relatively well. We did have a pretty good algae bloom in July while we were away on vacation, but following a lot of good advice in this forum on similar issues I was able to get clear water back in under a week.

I test almost daily using strips and about twice a week with a drop tester (not the preferred taylor as I have not been able to find it in Canada and i am not sure i can have liquid chemicals shipped over the border). I use Pucks in a chlorine feeder, and shock with liquid chlorine (11%)

Now I have slightly cloudy water that I cant seem to clear. I can see the bottom of the deep end, the water just isn't perfectly clear like it used to be.

So, off i go to the usual pool store with a water sample, and their printer is broken, so he just tells me my chlorine is a little high (which I knew because I turned the chlorine feeder up for a couple of days when i went away for the weekend to avoid another algae bloom - it is back to normal now), and everything else is pretty good "don't bother doing anything about it this late in the season and you will close the pool in a few weeks anyways" he says. He has no advice for the cloudiness, so I leave without buying anything.

We use the pool for 2 days and the cloudiness doesn't change, so fearing that it may be algea waiting to bloom, I added about 2.5 litres of 11% chlorine when we were done swimming on Saturday.

Yesterday, there is still no change so i go to a different pool store with a water sample, and here is what they told me;

FC = 9
CC = 9 (i called them back and they meant tc)
PH = 7.6
Alk = 90
CYA = 70
CH = 250

They tell me my stabilizer is high and the chlorine is high, so turn off the feeder and wait for the chlorine to fall to around a 2 - they are afraid i have chlorine lock. they think the cloudiness may be caused by too much stabilizer and chlorine. Wait for the chlorine to fall and if it doesnt clear then we can use a clarifier - i left the second pool store without buying anything

Based on what I have read on here, I know my stabilizer is high, but given the stabilizer of 70, a chlorine of 9 is within the target range - Is this correct? I fear 2 is too low for a CYA of 70

I have turned the chlorine feeder off so I do not increase CYA any further and will just use bleach (liquid chlorine) for the balance of the season.

I still fear this cloudiness is algae waiting to bloom, should I follow their advice and wait for the chlorine to fall, or should I ignore their advice and shock?

Thanks for your help, and sorry for the long post, i am trying to give as much info as possible.

Mike