question for any dutch growers

Get on all, i have a specific question for any dutch growers rergarding tap water in holland, what is your baseline tap water ec level, i know this may vary in different parts but a general indication of how hard the water is would be great, the reason i ask is that ive recently moved (not to holland unfortunately) from a moderately soft water area to a soft water area something that didnt even cross my mind until my plants displayed a calcium deficiency, grow shop guy said that canna which is the range i use in my aero setup is developed in holland where the water is very hard, i.e has a lot of calcium content, and im guessing the buffers they use for ph control also atach to calcium like bicarb of soda does, which would make the calcium level drop further.
i now use liquid calcium to bring my baseline ec up to 0.2 and every thing is groovy but id like to still know hollands water hardness (generally) thanks to anyone who can tell me this cheers