Is it normal for chlorine levels to drop off to zero in a couple of days. I had my chemicals balanced and 4 days later I tested the water and there was no chlorine. I thought if you have a cover on your spa that the chlorine won't dissipate so fast. Is this true.
Thanks

It depends on the chlorine level you had. There are lots of reasons why it would go down: if you have ozone, high water temp., bacteria in the spa, heavy usage, all these can dissipate chlorine.
I have a 350 gallon spa and I use a teaspoon on a daily basis if I use it daily - If not I get some in every 3 days.

I've been trying to keep it around 3-5 ppm. Every time i get it there and go back in a couple of days it reads 0 even without using it. I guess I'll go to a daily or every other day regiment to keep up with it. Thanks for your input.

You are absolutely right Peteboy. Not (yet) quite sure on how and why the Ozone will contribute to dissipate the Chlorine though, but I shall find out soon " title="Very Happy" />