Green Pool ???

[Lucywa]

Hello,

Our pool has gone green. We tried the algaecide.
There is a good amount of chlorine I think.
We have given it a good back wash.

I am not sure what else to test or try ...

Does anyone have any suggestions please?
Sorry if it is obvious!

Thanks,

Lucy

7.56PH
173mg/l TA
6.00 mg/l

 

[adridimo]

Hello Lucy,

do you have a measure of your CYA level?

You shoud follow the FC/CYA suggested level and SLAM your pool, try to have a look here, it works:

SLAM - Shock Level and Maintain

We’ve all had to deal with a green pool. Clear algae from your pool with a SLAM! Read here to use shock level and maintain to clear your pool.

www.troublefreepool.com

The Free Chlorine and Cyanuric Acid Relationship

Managing your cyanuric acid and Free Chlorine levels is key to stabilizing your pool. Learn how these two items affect each other.

www.troublefreepool.com

 

[jakeblat]

Hi Lucy,

Once you've tested your CYA with the PoolLab, if it's above 20 (which I'm guessing it will be) you'll be running into the limit of the maximum chlorine level the PoolLab 2.0 can't test for that would be needed to SLAM (their limit is 6ppm - you're almost certainly already higher than this).

You can perform a dilution test with the PoolLab using distilled water. I'm slightly surprised you're not getting an OR reading for chlorine but it's worth doing the diluted test to see what level you might actually be at. The diluted test isn't quite as accurate but will give you an idea.

From the manual:



Happy to help out as you're going to struggle to follow some of the TFP techniques with the test kits we have in the UK and the limited availability of some chemicals.

In your situation I would just empty the pool and give it a good clean with a bleach solution and refill - it'll be faster and cheaper than the amount of liquid chlorine/bleach you'd need - see Step 7 for seasonal pools Guide for Seasonal/Temporary Pools

 

[88Fluffhead]

Welcome.

Go to PoolSchool on this site- it is free and will save you hundreds. Read every article they take about an hour or so all together if you know a little about pools already.

Then get ready to SLAM that puppy.

I am a newbie here too, my pool was green and gross but it’s finally getting better after about a weeks worth of advice on this site. It’s a God Send!

 

[Lucywa]

Does this help ....

 

[Lucywa]

I think my CYA is 0 ...

 

[jakeblat]

@Lucywa Do you have any CYA tablets for the Pool Lab? It should have come with some in the starter pack. The test strips are not considered accurate enough to trust the results, but I've found the Pool Lab CYA test to be reasonably accurate.

 

[jakeblat]

I don't know if you're on Thames Water or Affinity (or if you're metered). But on a meter it would be between £33 (Affinity) -£41 (Thames) to empty and refill. With a pool that green it might take quite a bit of chlorine to clear it up following SLAM and you'd likely need to get hold of a better test kit to be able to follow the process (~£130). The refill might be easiest if you want to get a bit more out of the pool before it starts to cool down as the SLAM might take you a week or two, you also might end up spending more on the chlorine than the cost of the refill to get things back on track.

I buy liquid chlorine in bulk from Liquid Chlorine ChlorForce M15 -for Swimming Pools. They also sell on Amazon https://www.amazon.co.uk/ChlorForce-M15-Liquid-Chlorine-Swimming/dp/B0BJL3WRW1

Make sure you read the PoolSchool (Pool School) mentioned above so you understand the chlorine/CYA relationship and how that works with chlorine tablets vs liquid chlorine.

Do you plan to take the pool down over the winter or leave it up?

 

[Lucywa]

CYA is 90

 

[Lucywa]

Do you think empty and refill?
Or salvageable?

 

[jakeblat]

Definitely empty and refill. You need to get the CYA down and the only way to do that is to replace water, there are no chemicals you can add that will reduce this. That would mean replacing almost 70% of the water to reduce the CYA so you might as well empty it all the way and not have to do the SLAM.

Do make sure you follow the instructions I previously linked about seasonal pools about thoroughly cleaning everything before refilling otherwise you'll still have some hard work to do after refilling.

If you had a CYA of 30 you would have a target chlorine level of 4-6ppm. At a CYA of 90 your would have a target chlorine level of 10-12 (beyond what you can easily test with the Pool Lab). If you wanted to SLAM at CYA of 90 you'd need to maintain the chlorine level at 35 (which is way too difficult to test even with dilution with the Pool Lab)

 

[jakeblat]

@Lucywa Did you end up refilling and getting things back under control?