The Pink Colors
As sea water is pumped into the first evaporating ponds, or condensers, the color is that of sea water, being very transparent and reflecting the color of the ponds’ bottoms. As the water flows to the following condensers, evaporating on the way and thereby increasing its salinity, algae start to grow and flourish. This shows the characteristic green colored ponds. As the flow continues and additional evaporation takes place and the salinity increases further, the algae die and this is shown in a brown color.
Finally as the water becomes saturated in salt, now so called ‘brine’, it is pumped into the crystallizing ponds where upon further evaporation the salt crystallizes and forms a salt layer on the floors, which eventually is harvested. In these ponds we see the characteristic pink color which is caused a microorganism called halophilic bacteria, which thrive in high salinity brine and in reality are not bacteria but single cell life-forms.
They have no effect on the quality of the salt. The cell membranes contain carotenoid pigments which give the crystallizers the pink-red color. The dark color increases the absorption of sun light which increases the temperature which in turn increase evaporation and salt production.