[TonyR]

Hiya
Any salt that when mixed delivers levels at or close to NSW. IO for instance needs adjusting so that means adding chlorides,sodium and Sulphates from the bucket.
So we mix up our salt to 1.025, check the levels and find we are low. We then add Calcium chloride,Sodium Bicarb/carbonate and Mag Chloride/Sulphate to the mix. Chlorides then get bumped up thus increasing salinity, sulphates and sodium(due to the Sodium Bicarb) also increases.
Now add to that a two part additive regime and one could find those ionic levels slowly creeping up over time.
As for a balanced salt then H20 pretty much hits the spot with regards to NSW levels out of the bucket.
Ive never been a fan of two part dosing due to the fact that without water changes chlorides, sodium etc can become elevated over time. How long might it take? I couldnt tell you but seeing as you cant tell or test then its pretty much a lottery imo.
The chlorides used in H20 are slightly lower, this allows for the addition of chlorides such as Magnesium Chloride or Calcium chloride if you choose to use as a two part method for your Ca/Alk regime.