Roan,
I worried about this too, that the process of water softening involves an exchange with salts, but when I went searching on the internet I could not find any references to it other than a few people discussing getting a water softener for their aquarium water... I wonder now if they really meant an RO system. So, I suppose too quickly, I assumed that I was just ignorant of the whole chemical picture of water softening or that the sodium ions that are exchanged are not in the form of NaCl and therefore not a problem, or something. I guess it's time to reconsider the problem...
So are you saying that I essentially have my fish in brackish water right now? Since I do not want a live bearer tank (BTW to those who were discussing this.. guppies, do best in water that is over 7.5 and hard, if there is some salt all the better.) Is a 100% water change with RO the solution? I can get it at my local grocery for $.40 a gallon so it's not a big deal to do that... just four trips with my 10 refill jugs, right around the corner form my house. The water, unsoftened out of the tap (i.e. from the well), has a PH that is well above 8 and off the scale hard. (Again, before I was trying to keep it lower for the ottos my 5.5 guppies loved it that way... never got sick, bred like crazy.. I am planning to trade the new 1/2 black blue babies for credits at my LFS I can use for fish in the 37 Tetra tank.)
HappyChem,
Thank you very much. I know, as you said, that your explanation is a simplified version of the detail, but it is much more complex an explanation than I have found thus far of what is going on with Hardness, KH, GH, PH etc. Even if I am ultimately to decide not to worry about my PH much, I am at heart still an academic. I want to know as much as I can anyway, and I believe that all problems have a logical answer... as opposed to "Well, Ottos just don't do well, don't know why, but pay no attention to the high PH behind the curtain".
To everyone in the Otto part of the discussion,
I think the deal with Ottos is a combination of stress (not being fed well, etc) during shipment, as HappyChem mentioned, and that they don't take acclimating to a new set of parameters well (maybe because they are so bad off from shipment?). I went through several pairs in the 5.5 with the normal float the bag, add little bit of water, thing. Then finally I talked to my family-owned-FS and got extra water in the bag. I set up a slow drip, through air type tubing crimped with those lead weights they use at Corperate-FSs for plants, to a small bucket of the water they came in. They both lived through the process and are now very hardy fish, who are invaluable in my high-light, little, planted 5.5. They are fun to watch, loosely school together, will guard a strawberry or zucchini with their lives

, and they keep both the tank and the plants algae free without harming them or disturbing the landscaping (i.e. digging). I think they are well worth the effort