english: SPF 30 is not going to do anything  to you over there, and the water is so transparent in those lakes that the algae has nowhere to hide, really, and so they are developing their own sunscreen, and this is the red color you see.
non_english: Factor 30 anti-zonnebrand is daar nutteloos en het water van de meren is zo helder dat de algen zich nergens kunnen verstoppen, dus maken ze hun eigen anti-zonnebrand aan. Dat is de rode kleur die je ziet.