I checked at a Leslies Pool Supply in Phoenix, AZ, where you would expect a full range of pool and spa products to be frequently used. They did not know what I was talking about when I asked for Hydrogen Peroxide, and the Baqua Spa oxidizer was the only thing they had. So 7.5% is likely to be the strongest you can get at a pool supply, and that hardly seems worth the extra cost.
Mike
--- In Homebrew_PCBs@yahoogroups.com, "Jim" <jhancock1@...> wrote:
>
> Baqua spa oxidizer. However, I made a mistake on the concentration -it's only 7.5% . Getting old, memory not what it used to be.