Hi Lanzo - just to confirm - you fell in the EXACT same trap as MOST newby marine-keepers start out with - including myself..... I used a lot of the above as well, until I learnt otherwise......
The guys have said it all - and this once again proves my point - MOST LFS people are not reefkeepers and neither are they passionate about reefs.... so they FAR less that even you or I.... Could not even compare them to some guru's on this site....
So - glad you asked.... and you got your answers...
BTW: you can use Slaked Lime (Gebluste Kalk) which you can get at any chemist to make up your kalkwasser - yes, there are far more expensive forms of kalkwasser out there..... BUT I have been getting GREAT results from slaked lime (this is Calcium Hydroxide)...... JUST BE VERY CAREFUL WITH THE DOSAGES! ASK BEFORE YOU USE IT.
Also, to keep your alkalinity in the water up: Baking SODA (Sodium Bicarbonate)....
Whatever change you make - JUST MAKE IT SLOWLY!
Good luck!