Larry,

This a complex question, that we recently addressed at great length. Instead of putting all that info here, I'm going to do what I should have done then, and write a general page I can post on PoolSolutions.

Meanwhile, in order to apply that information to your situation, I need some specific info from you:

1. Do you cover your pool? Is it enclosed?
2. PRECISELY what chemicals are you adding to both pool and spa? (Many times, "pool chlorine" includes problematic mystery chemicals.)
3. Do you use ANY of the following: non-chlorine shock, 'mineral' treatment, skimmer pills, algaecides, or stain treatments. If so, EXACTLY which products are you using?
4. How do you test your water? How often?
5. Which MODEL Delozone unit do you have (EC-4 -- a 1gm/hr unit) ? Do you have a degas chamber installed, downstream of the ozonator.
6. Are you aware that ozone is a HIGHLY toxic gas, which triggers respiratory distress in sensitive individuals?
(Pool "ozone" is precisely the same chemical that is present in the air, when cities issue "ozone alerts" in the summer time. Ozone is considerably MORE toxic than chlorine gas!)
7. Have you ever noticed bubbles coming out of the returns, into the pool? Have you ever noticed the odor of ozone near the pool inlet closest to the pool equipment?
8. How far is it, in feet, from the ozone venturi, to the nearest return inlet in the pool?
9. Have you ever tried using the pool, after turning the ozonator OFF for 2 days, but while continuing to maintain chlorine levels?

Meanwhile, I'll start on the chlorine allergy page.