Complex sentence: Due to the 2011 drought affecting Texas, the water had taken on a reddish hue, caused by bacteria of the Chromatiaceae, which were thriving in the oxygen-deprived water.
Split into simpler sentences: Due to the 2011 drought affecting Texas, the water had taken on a reddish hue. The red color was caused by the bacteria Chromatiaceae, which was thriving in the oxygen-deprived water.