My tap water is a somewhat alkaline, as is the dust that gets blown into my pool here in the desert. So I never have to add either borax or baking soda - except when I used some tri-chlor to bump up my CYA, and then only a very small amount, less than a cup. I occasionally have to add acid to bring my PH down, but even that's really not a whole lot, just a few ounces every couple of weeks. That's one thing I like about liquid chlorine (bleach) - although it has a high PH, the chemical reaction of the chlorine is low PH, so it tends to balance itself out.
Oh, and depending on where you are in the country, you might be able to find the 10 or 12 percent liquid chlorine cheaper than bleach. I usually get the Kem-Tek brand of 10% at Home Depot or Lowes. But liquid chlorine at the pool store is often more expensive here, and doesn't seem to be as fresh.