Yep. 100% cal hypo contains -- usually -- 67% available chlorine.

Avoid the cal hypo blends. And if you are wondering, yes, they are trying to trick you. The 'other ingredients' are considerably cheaper than cal hypo, by the pound.

The ozone system sounds like it's a suction side (in front of the pump) air inlet. Those type systems continuously aerate the pool, and make it impossible to maintain recommended levels of carbonate alkalinity. However, this is only a problem on concrete (plaster, etc.) pools.

PoolDoc