low CYA low Chlorine vs. Higher CYA Higher Chlorine

[crazycanuck]

right now my readings are

FC 1.88
CC 0.2
TC 2.04
CYA 30
alk 110
pH 7.8

The SWG is an IC20 running at 60%
we have had lots of sun for the last week
The pool is crystal clear and the pump runs for
approx 16 hours a day.

Now, should I try and increase my chlorine to 3-4ppm with that CYA or
increase the CYA to 50 and bump the chlorine to 5ppm... does .2 warrant shocking? The water is clear and no signs of algae.

Do you think with such a borderline CYA that my chlorine is getting consumed by the sun quickly, hence my lower chlorine count?

 

[JasonLion]

If you raise your CYA up to 60 you will be able to run your SWG on a lower power setting and only need to increase the FC level a little. I suggest CYA 60 and FC 3. SWG systems allow you to run the FC level a little below the min level on the best guess chart. This works partly because the chlorine level is more uniform with a SWG, it doesn't have the large daily swing in FC level that adding bleach once a day causes. And the cell super chlorinates a small portion of the water as it passes through the cell helping to keep your CC level under control.

 

[crazycanuck]

so do you think because my CYA is only at 30 that my FC is only at 2.0 due to sun burnoff?

 

[JasonLion]

Yes. It is much easier to maintain a chlorine level with a SWG if the CYA level is towards the higher end of the range. Pentair recommends a CYA level of between 50 and 75.