In this task, we ask you to elaborate the sentence without changing its general meaning. You can do so by explaining further the input sentence, using more precise wording, adding qualifiers and auxiliary information etc.

During winter the lake water becomes well mixed , and the lake water is less clear because of tannins and calcium carbonate particles .
During winter , the lake becomes well mixed , and recent research indicates that during this phase of the colour cycle , the lake is somewhat murkier due to the redistribution of tannins and calcium carbonate particles throughout the lake .