As much as I'd be grateful for another Lifetime Membership, if your primary concern is with a spa, I'm not sure I'd recommend that you purchase one. Neither I, nor most of the moderators, have a lot of spa experience . . . and spa chemistry is rather different.

So while the general BBB approach can work for spas, the details are something you may have to work out yourself. I'm glad that you seem to be succeeding with that now, but I don't want to 'oversell' you on what the PoolForum can offer.