What is a cheaper Shock to use?

[70MM]

Im in new Zealand so not all products sugested on here maybe available to me. I have a spa with ozone and I use Aquacadabra as I dont want any chemicals in it. I was using one of their Shocks for the pool once a week but it is so expensive!!! Anyone sugest to me something cheaper to use as a Shock please?

[hottub.pool_boy]

I'll take a stab at this.

If you want a sanitizing method with no chlorine/ bromine or little chlorine/ bromine you're going to pay more.

Try using traditional sanitizing methods, ie. chlorine/ bromine they're less expensive and try to get over the idea that you're using toooo many chemicals.

Dichlor and granular bromine are great methods and you don't use much.

[wmccall]

One thing on Chemicals, product names can vary quite a bit and I can't keep track of them all. I don't know about down there, but look at the ingredients, and look at the dosage.  Many spa chemicals, such as MPS  are buffered to prevent changes in PH.  An example, some MPS say 50% inert ingredients.  For my size tub they suggest to use 4 ounces.  Another brand is 100% MPS and I can use 1/2 as much.  I can deal with the change in PH and use less in cost and chemical volume by using the 100% shock.