Chlorine Question??

[mkfmedic]

Hi folks,

It has been relatively easy pool summer and as the weather cools, I am running into an issue I did not expect.

My pool is approximately 10,500 gallons (15' X 21', 7' raised spa with spillway, 3' - 5' deep, uses SWCG (Jandy 1400, set at 30% output), a DelOzone II system, Jandy DE 60 filter and the water is circulated through a 2 HP pump, which runs 6 hours a day. I also have 6' of sheer descents which automatically turn on for two hours each day.

The last two tests, I have shown the following chlorine results:

FC-9
CC-0
TC-9

After the first test with these results at the end of last month, I turned off my Jandy SWCG for four days. When I came home, I set it 5% and re-tested the pool this morning. The chlorine has not changed. The rest of the results:

pH - 7.8
Alk - 70
Cal - 370
CYA - 70
Salt - 3400

Is it possible that with the cool weather, except the last two days here in So. Cal, that the Ozone system is managing the needs of the pool with the available chlorine? At what level of chlorine do I need to begin to worry?

Should I just turn off the SWCG, or just leave it at its lowest level at 5%?

Anyway, as always, I appreciate your thoughts, advice and input!

Best Regards,

Mike

[aylad]

I doubt seriously that the ozone system has anything to do with it. At lower temperatures, your chlorine usage is going to greatly decrease. In your pool, I would maintain 5 ppm. Whether you want to do it by running your SWC or by manually adding bleach once in awhile is up to you.

Janet