Ozone Pool Questions...

[bj701]

Hi,

I've taken on looking after a friends pool. It's in-ground, lined, 25000L, Ozone system + chlorine tablets (trichlor) - about 2 year old. Location, Adelaide, Australia.

Went to see a guy at the local pool shop today and he is skeptical of the ozone system and says I should just ignore it and do the more traditional method of a daily cup of powder and trickle feed with the tablets. He seems to think the chlorine levels will not be adequate, especially through a long hot Aussie summer.

The ozone system was originally purchased in the hope of using less chlorine = better on the skin and eyes etc.

As I'm taking over maintaining the pool, my question is: How do I know if the ozone+chlorine tablets are providing the right amount of chlorine?

I have the paper indicators to test, but, are these the right way to test the overall chlorine levels for this type of system?

and... Do I need to use stabilizer? What effect does it perform? How do I know if i have the right level?

Appreciated, Brett.

[chem geek]

For a low bather-load residential pool, ozone will not save on chlorine nor do much good. As noted in the paper Chemistries of Ozone for Municipal Pool and Spa Water Treatment, ozone reacts with chlorine creating oxygen gas, chloride, and chlorate.

Most chlorine loss in outdoor residential swimming pools is due to sunlight, not to bather load, so ozone won't save on chlorine usage. Ozone makes sense to use in high bather-load situations such as in residential spas that are used every day or two.

Test strips are not generally accurate for testing. You should consider a better drop-based test kit, the best being the Taylor K-2006 but you cannot get that in Australia easily though see this link where you can get a K-2005C which isn't bad, but a FAS-DPD chlorine test would be better.

As for what FC level to have in the pool, that depends on the CYA level so I suggest you read the Pool School.