Ozone generator from mercury vapor bulb

Hello,

I found plans to a ozone (UV) generator that uses a mercury vapor bulb with the outer glass broken away to produce ozone. The problem I am having is that it produces a greenish light that seems to produce at best low amounts (if any) of ozone. Has anyone else had any success with this type of ozone generator? I wanted to use it to ozone water in a small pool, instead of chlorine. Any help would be greatly appreciated.

Thanks!!!