Hi Riley,
I was ALSO told that Bacqua Spa causes corrosion of the seals, (by a hot tub sales person who doesn't carry their products) however, what I learned with more research was EXCESSIVE USE OF SANITIZER *MAY* CAUSE CORROSION. I've been using Bacqua Spa products for the past 3 years and I LOVE them!!!
They are clean, no smells, no chlorine, no burning eyes or skin irritation, and I CAREFULLY apply just enough of the sanitizer to keep my hot tub in compliance with recommendations and I haven't had any problems whatsoever!
Hope this helps!
Jeff from Sonoma's Wine Country