Jerry,
I grew "traditionally" for some 25 years before developing s/h culture as a way to keep my plants alive while I traveled (I averaged 13 flights a week for about 3.5 years, at one point).
- I think you need not worry about your water quality.
- Most water supplies do have plenty of calcium and magnesium.
- That fertilizer will be fine.
- That mid-to-upper sixes pH isn't so far off that it would be a strain on the plants, but if you want to lower it further, I have heard of folks using vinegar.
- I have a similar collection. Not all of it is in S/H culture, so don't feel a need to do a "mass conversion". In fact, I recommend against it.
Select a plant that is just breaking new roots, and try that one. Be patient, pay attention to details, and pretty soon you'll understand that it's just different. After that, consider more.