Chemistry Good, Water Green

[Dougget]

Hi all,
I have a vinyl IG pool. 19,400 Gal. Sand Filter.
I test my water regularly with the TF-100 kit and periodically take water to the pool store for a test. They need a record of my chemistry to support equipment warranty requirements. Anyway, my water is usually fine when they test it, and theirs tests are usually pretty close to my own results.

I tested my water last night and got the following results:

FC	6
pH	8.2
CC	0.5
TC	6.5
TA	120
CH	150
CYA	0

I added some acid and stabilizer after my test and the pool store test shows the following results
FC 1.9
pH 7.6
CC 2.2
TA 115
CYA 46
CH 100

So everything looks great... except my water is still green.

What do you recommend?

Thanks,
Doug

 

[YippeeSkippy]

Something is definitely wrong if adding acid took your FC from 6 down to 1.9. . All those results are questionable.

No matter how things are wrong, the cure is still a SLAM procedure. Please review this: SLAM Process

Maddie

 

[Poolzzz]

So everything looks great... except my water is still green.

Actually they are not great at all. For algae, fc and cya matter. Your fc is too low for the cya level. Look up the FC/CYA chart in pool school for the correct levels.

As stated above, to fix the green you need to SLAM.

When you slam is complete then make sure you maintain your fc at the proper level as per the FC/CYA chart in pool school. Dose to the target values and NEVER ever let it go below the minimum if you want to avoid algae.

Also use your tf100 testkit, not pool store results. For cya tests round up to even tens (40, 50, 60 etc). When doing fc tests use 10ml sample for 0.5ppm resolution.