You CAN dose Sodium Hydroxide (not sure why on earth anyone would do it) it will boost alk but not calcium thus causing an imbalance, therefore Calcium Hydroxide is the winner still
by the way, important to point out some safety notes with pickling lime, yes it's for consumption but the powder itself isn't safe on its own, here's a sniped from Randy's article on kalkwasser;
"Lime Safety
On the negative side, limewater does have some safety concerns that don’t apply to most other calcium and alkalinity additive systems. The high pH of the liquid and the dust hazard of the solid are not to be treated lightly. Inhalation of the dust is to be avoided. Splashing limewater onto skin is also to be avoided, and should be followed by extensive rinsing with tap water if it happens. Splashing limewater into the eyes is especially to be avoided, and the use of safety goggles is prudent when using large amounts or in situations where exposure is likely. Extensive and immediate rinsing with tap water, followed by professional help, would be advised in the case of eye exposure. Keep in mind that the slippery feeling that a high pH liquid such as limewater causes on your hands is due to the breakdown of the fats in the skin into fatty acids (which are soaps).
Quicklime has some special hazards beyond normal lime and limewater. Specifically, these relate to the heat produced when calcium oxide hydrates to form calcium hydroxide. A small amount of water added to a significant amount of quicklime will get very hot. It can even boil. Some aquarists have melted Nilsen reactors this way, and some have had such reactors “explode,” presumably through rapid heating and pressure buildup. So when using calcium oxide, be sure to add a small amount of lime to a significantly larger amount of water."
That last line is important, do not add water to pickling lime but always add the pickling lime to your container already filled with water. I've also inhaled pickling lime dust by accident before, cough & cough & cough & cough & cough, it's not fun.
