My neighbor indicates he uses bleach and vinegar as substitutes for chlorine and/or bromine. He indicates he has good water chemistry. In our city, we have high alkalinity.

Is there a problem doing this? What are the pros? What are the cons? Any general water tips?

vinegar is an old recommendation for lowering ph, and it still works. white vinegar is best. bleach should be left to swimming pools, although the vinegar will combat bleach's high ph.

Personally, I use muratic acid for lowering ph. It is less odorous and takes a lot less to perform the same function. It is a lot stronger so use caution when handeling. I use that inflateable pool shock for my chlorine, it is a lot higher concentration than the standard chlorine used in spas (same exact chemical compostion) but has less of the inert ingredients that throw off the spa's ph.

White vinegar or concentrated lemon juice (no pulp) will lower your pH, while common baking soda will raise it. Check your spa’s instruction manual to make sure it does not specifically forbid these methods before implementing.