The titration curves with different additives (citric, tartaric, and succinic acid) at concentrations of 2, 6, and 10 mM are shown in Figure . As mentioned above, the molecules' stabilizing effects on calcium hydroxide prenucleation clusters manifest themselves in decreased initial slopes of the curve before the maximum. The slopes of all curves in Figure were calculated for the linear part before the maximum (Table ). As the slopes of all curves with low and medium concentrations are equal to the reference, the additives do not significantly increase the stability of the initial prenucleation clusters compared to the reference. Only the curves with the highest additive concentration show slight differences that are still within the measurement error. Instead, the curves show a local minimum at the beginning of the &D$GGHGPPRO/ -1 experiment, followed by a linear increase in calcium concentration similar to phase I in the reference experiment. As the linear part of the curves is only shifted along the x-axis to the reference, without significant changes in the slope of the curve, the experimental data indicate the calcium complexation by the additives.